Merging upstream version 125.0.1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

26 files changed, 8259 insertions, 0 deletions

diff --git a/third_party/python/Mako/mako/__init__.py b/third_party/python/Mako/mako/__init__.py
new file mode 100644
index 0000000000..16d187c0ce
--- /dev/null
+++ b/third_party/python/Mako/mako/__init__.py
@@ -0,0 +1,8 @@
+# mako/__init__.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+
+__version__ = '1.1.2'
diff --git a/third_party/python/Mako/mako/_ast_util.py b/third_party/python/Mako/mako/_ast_util.py
new file mode 100644
index 0000000000..bdcdbf6913
--- /dev/null
+++ b/third_party/python/Mako/mako/_ast_util.py
@@ -0,0 +1,716 @@
+# mako/_ast_util.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""
+    ast
+    ~~~
+
+    This is a stripped down version of Armin Ronacher's ast module.
+
+    :copyright: Copyright 2008 by Armin Ronacher.
+    :license: Python License.
+"""
+
+
+from _ast import Add
+from _ast import And
+from _ast import AST
+from _ast import BitAnd
+from _ast import BitOr
+from _ast import BitXor
+from _ast import Div
+from _ast import Eq
+from _ast import FloorDiv
+from _ast import Gt
+from _ast import GtE
+from _ast import If
+from _ast import In
+from _ast import Invert
+from _ast import Is
+from _ast import IsNot
+from _ast import LShift
+from _ast import Lt
+from _ast import LtE
+from _ast import Mod
+from _ast import Mult
+from _ast import Name
+from _ast import Not
+from _ast import NotEq
+from _ast import NotIn
+from _ast import Or
+from _ast import PyCF_ONLY_AST
+from _ast import RShift
+from _ast import Sub
+from _ast import UAdd
+from _ast import USub
+
+from mako.compat import arg_stringname
+
+BOOLOP_SYMBOLS = {And: "and", Or: "or"}
+
+BINOP_SYMBOLS = {
+    Add: "+",
+    Sub: "-",
+    Mult: "*",
+    Div: "/",
+    FloorDiv: "//",
+    Mod: "%",
+    LShift: "<<",
+    RShift: ">>",
+    BitOr: "|",
+    BitAnd: "&",
+    BitXor: "^",
+}
+
+CMPOP_SYMBOLS = {
+    Eq: "==",
+    Gt: ">",
+    GtE: ">=",
+    In: "in",
+    Is: "is",
+    IsNot: "is not",
+    Lt: "<",
+    LtE: "<=",
+    NotEq: "!=",
+    NotIn: "not in",
+}
+
+UNARYOP_SYMBOLS = {Invert: "~", Not: "not", UAdd: "+", USub: "-"}
+
+ALL_SYMBOLS = {}
+ALL_SYMBOLS.update(BOOLOP_SYMBOLS)
+ALL_SYMBOLS.update(BINOP_SYMBOLS)
+ALL_SYMBOLS.update(CMPOP_SYMBOLS)
+ALL_SYMBOLS.update(UNARYOP_SYMBOLS)
+
+
+def parse(expr, filename="<unknown>", mode="exec"):
+    """Parse an expression into an AST node."""
+    return compile(expr, filename, mode, PyCF_ONLY_AST)
+
+
+def iter_fields(node):
+    """Iterate over all fields of a node, only yielding existing fields."""
+    # CPython 2.5 compat
+    if not hasattr(node, "_fields") or not node._fields:
+        return
+    for field in node._fields:
+        try:
+            yield field, getattr(node, field)
+        except AttributeError:
+            pass
+
+
+class NodeVisitor(object):
+
+    """
+    Walks the abstract syntax tree and call visitor functions for every node
+    found.  The visitor functions may return values which will be forwarded
+    by the `visit` method.
+
+    Per default the visitor functions for the nodes are ``'visit_'`` +
+    class name of the node.  So a `TryFinally` node visit function would
+    be `visit_TryFinally`.  This behavior can be changed by overriding
+    the `get_visitor` function.  If no visitor function exists for a node
+    (return value `None`) the `generic_visit` visitor is used instead.
+
+    Don't use the `NodeVisitor` if you want to apply changes to nodes during
+    traversing.  For this a special visitor exists (`NodeTransformer`) that
+    allows modifications.
+    """
+
+    def get_visitor(self, node):
+        """
+        Return the visitor function for this node or `None` if no visitor
+        exists for this node.  In that case the generic visit function is
+        used instead.
+        """
+        method = "visit_" + node.__class__.__name__
+        return getattr(self, method, None)
+
+    def visit(self, node):
+        """Visit a node."""
+        f = self.get_visitor(node)
+        if f is not None:
+            return f(node)
+        return self.generic_visit(node)
+
+    def generic_visit(self, node):
+        """Called if no explicit visitor function exists for a node."""
+        for field, value in iter_fields(node):
+            if isinstance(value, list):
+                for item in value:
+                    if isinstance(item, AST):
+                        self.visit(item)
+            elif isinstance(value, AST):
+                self.visit(value)
+
+
+class NodeTransformer(NodeVisitor):
+
+    """
+    Walks the abstract syntax tree and allows modifications of nodes.
+
+    The `NodeTransformer` will walk the AST and use the return value of the
+    visitor functions to replace or remove the old node.  If the return
+    value of the visitor function is `None` the node will be removed
+    from the previous location otherwise it's replaced with the return
+    value.  The return value may be the original node in which case no
+    replacement takes place.
+
+    Here an example transformer that rewrites all `foo` to `data['foo']`::
+
+        class RewriteName(NodeTransformer):
+
+            def visit_Name(self, node):
+                return copy_location(Subscript(
+                    value=Name(id='data', ctx=Load()),
+                    slice=Index(value=Str(s=node.id)),
+                    ctx=node.ctx
+                ), node)
+
+    Keep in mind that if the node you're operating on has child nodes
+    you must either transform the child nodes yourself or call the generic
+    visit function for the node first.
+
+    Nodes that were part of a collection of statements (that applies to
+    all statement nodes) may also return a list of nodes rather than just
+    a single node.
+
+    Usually you use the transformer like this::
+
+        node = YourTransformer().visit(node)
+    """
+
+    def generic_visit(self, node):
+        for field, old_value in iter_fields(node):
+            old_value = getattr(node, field, None)
+            if isinstance(old_value, list):
+                new_values = []
+                for value in old_value:
+                    if isinstance(value, AST):
+                        value = self.visit(value)
+                        if value is None:
+                            continue
+                        elif not isinstance(value, AST):
+                            new_values.extend(value)
+                            continue
+                    new_values.append(value)
+                old_value[:] = new_values
+            elif isinstance(old_value, AST):
+                new_node = self.visit(old_value)
+                if new_node is None:
+                    delattr(node, field)
+                else:
+                    setattr(node, field, new_node)
+        return node
+
+
+class SourceGenerator(NodeVisitor):
+
+    """
+    This visitor is able to transform a well formed syntax tree into python
+    sourcecode.  For more details have a look at the docstring of the
+    `node_to_source` function.
+    """
+
+    def __init__(self, indent_with):
+        self.result = []
+        self.indent_with = indent_with
+        self.indentation = 0
+        self.new_lines = 0
+
+    def write(self, x):
+        if self.new_lines:
+            if self.result:
+                self.result.append("\n" * self.new_lines)
+            self.result.append(self.indent_with * self.indentation)
+            self.new_lines = 0
+        self.result.append(x)
+
+    def newline(self, n=1):
+        self.new_lines = max(self.new_lines, n)
+
+    def body(self, statements):
+        self.new_line = True
+        self.indentation += 1
+        for stmt in statements:
+            self.visit(stmt)
+        self.indentation -= 1
+
+    def body_or_else(self, node):
+        self.body(node.body)
+        if node.orelse:
+            self.newline()
+            self.write("else:")
+            self.body(node.orelse)
+
+    def signature(self, node):
+        want_comma = []
+
+        def write_comma():
+            if want_comma:
+                self.write(", ")
+            else:
+                want_comma.append(True)
+
+        padding = [None] * (len(node.args) - len(node.defaults))
+        for arg, default in zip(node.args, padding + node.defaults):
+            write_comma()
+            self.visit(arg)
+            if default is not None:
+                self.write("=")
+                self.visit(default)
+        if node.vararg is not None:
+            write_comma()
+            self.write("*" + arg_stringname(node.vararg))
+        if node.kwarg is not None:
+            write_comma()
+            self.write("**" + arg_stringname(node.kwarg))
+
+    def decorators(self, node):
+        for decorator in node.decorator_list:
+            self.newline()
+            self.write("@")
+            self.visit(decorator)
+
+    # Statements
+
+    def visit_Assign(self, node):
+        self.newline()
+        for idx, target in enumerate(node.targets):
+            if idx:
+                self.write(", ")
+            self.visit(target)
+        self.write(" = ")
+        self.visit(node.value)
+
+    def visit_AugAssign(self, node):
+        self.newline()
+        self.visit(node.target)
+        self.write(BINOP_SYMBOLS[type(node.op)] + "=")
+        self.visit(node.value)
+
+    def visit_ImportFrom(self, node):
+        self.newline()
+        self.write("from %s%s import " % ("." * node.level, node.module))
+        for idx, item in enumerate(node.names):
+            if idx:
+                self.write(", ")
+            self.write(item)
+
+    def visit_Import(self, node):
+        self.newline()
+        for item in node.names:
+            self.write("import ")
+            self.visit(item)
+
+    def visit_Expr(self, node):
+        self.newline()
+        self.generic_visit(node)
+
+    def visit_FunctionDef(self, node):
+        self.newline(n=2)
+        self.decorators(node)
+        self.newline()
+        self.write("def %s(" % node.name)
+        self.signature(node.args)
+        self.write("):")
+        self.body(node.body)
+
+    def visit_ClassDef(self, node):
+        have_args = []
+
+        def paren_or_comma():
+            if have_args:
+                self.write(", ")
+            else:
+                have_args.append(True)
+                self.write("(")
+
+        self.newline(n=3)
+        self.decorators(node)
+        self.newline()
+        self.write("class %s" % node.name)
+        for base in node.bases:
+            paren_or_comma()
+            self.visit(base)
+        # XXX: the if here is used to keep this module compatible
+        #      with python 2.6.
+        if hasattr(node, "keywords"):
+            for keyword in node.keywords:
+                paren_or_comma()
+                self.write(keyword.arg + "=")
+                self.visit(keyword.value)
+            if getattr(node, "starargs", None):
+                paren_or_comma()
+                self.write("*")
+                self.visit(node.starargs)
+            if getattr(node, "kwargs", None):
+                paren_or_comma()
+                self.write("**")
+                self.visit(node.kwargs)
+        self.write(have_args and "):" or ":")
+        self.body(node.body)
+
+    def visit_If(self, node):
+        self.newline()
+        self.write("if ")
+        self.visit(node.test)
+        self.write(":")
+        self.body(node.body)
+        while True:
+            else_ = node.orelse
+            if len(else_) == 1 and isinstance(else_[0], If):
+                node = else_[0]
+                self.newline()
+                self.write("elif ")
+                self.visit(node.test)
+                self.write(":")
+                self.body(node.body)
+            else:
+                self.newline()
+                self.write("else:")
+                self.body(else_)
+                break
+
+    def visit_For(self, node):
+        self.newline()
+        self.write("for ")
+        self.visit(node.target)
+        self.write(" in ")
+        self.visit(node.iter)
+        self.write(":")
+        self.body_or_else(node)
+
+    def visit_While(self, node):
+        self.newline()
+        self.write("while ")
+        self.visit(node.test)
+        self.write(":")
+        self.body_or_else(node)
+
+    def visit_With(self, node):
+        self.newline()
+        self.write("with ")
+        self.visit(node.context_expr)
+        if node.optional_vars is not None:
+            self.write(" as ")
+            self.visit(node.optional_vars)
+        self.write(":")
+        self.body(node.body)
+
+    def visit_Pass(self, node):
+        self.newline()
+        self.write("pass")
+
+    def visit_Print(self, node):
+        # XXX: python 2.6 only
+        self.newline()
+        self.write("print ")
+        want_comma = False
+        if node.dest is not None:
+            self.write(" >> ")
+            self.visit(node.dest)
+            want_comma = True
+        for value in node.values:
+            if want_comma:
+                self.write(", ")
+            self.visit(value)
+            want_comma = True
+        if not node.nl:
+            self.write(",")
+
+    def visit_Delete(self, node):
+        self.newline()
+        self.write("del ")
+        for idx, target in enumerate(node):
+            if idx:
+                self.write(", ")
+            self.visit(target)
+
+    def visit_TryExcept(self, node):
+        self.newline()
+        self.write("try:")
+        self.body(node.body)
+        for handler in node.handlers:
+            self.visit(handler)
+
+    def visit_TryFinally(self, node):
+        self.newline()
+        self.write("try:")
+        self.body(node.body)
+        self.newline()
+        self.write("finally:")
+        self.body(node.finalbody)
+
+    def visit_Global(self, node):
+        self.newline()
+        self.write("global " + ", ".join(node.names))
+
+    def visit_Nonlocal(self, node):
+        self.newline()
+        self.write("nonlocal " + ", ".join(node.names))
+
+    def visit_Return(self, node):
+        self.newline()
+        self.write("return ")
+        self.visit(node.value)
+
+    def visit_Break(self, node):
+        self.newline()
+        self.write("break")
+
+    def visit_Continue(self, node):
+        self.newline()
+        self.write("continue")
+
+    def visit_Raise(self, node):
+        # XXX: Python 2.6 / 3.0 compatibility
+        self.newline()
+        self.write("raise")
+        if hasattr(node, "exc") and node.exc is not None:
+            self.write(" ")
+            self.visit(node.exc)
+            if node.cause is not None:
+                self.write(" from ")
+                self.visit(node.cause)
+        elif hasattr(node, "type") and node.type is not None:
+            self.visit(node.type)
+            if node.inst is not None:
+                self.write(", ")
+                self.visit(node.inst)
+            if node.tback is not None:
+                self.write(", ")
+                self.visit(node.tback)
+
+    # Expressions
+
+    def visit_Attribute(self, node):
+        self.visit(node.value)
+        self.write("." + node.attr)
+
+    def visit_Call(self, node):
+        want_comma = []
+
+        def write_comma():
+            if want_comma:
+                self.write(", ")
+            else:
+                want_comma.append(True)
+
+        self.visit(node.func)
+        self.write("(")
+        for arg in node.args:
+            write_comma()
+            self.visit(arg)
+        for keyword in node.keywords:
+            write_comma()
+            self.write(keyword.arg + "=")
+            self.visit(keyword.value)
+        if getattr(node, "starargs", None):
+            write_comma()
+            self.write("*")
+            self.visit(node.starargs)
+        if getattr(node, "kwargs", None):
+            write_comma()
+            self.write("**")
+            self.visit(node.kwargs)
+        self.write(")")
+
+    def visit_Name(self, node):
+        self.write(node.id)
+
+    def visit_NameConstant(self, node):
+        self.write(str(node.value))
+
+    def visit_arg(self, node):
+        self.write(node.arg)
+
+    def visit_Str(self, node):
+        self.write(repr(node.s))
+
+    def visit_Bytes(self, node):
+        self.write(repr(node.s))
+
+    def visit_Num(self, node):
+        self.write(repr(node.n))
+
+    # newly needed in Python 3.8
+    def visit_Constant(self, node):
+        self.write(repr(node.value))
+
+    def visit_Tuple(self, node):
+        self.write("(")
+        idx = -1
+        for idx, item in enumerate(node.elts):
+            if idx:
+                self.write(", ")
+            self.visit(item)
+        self.write(idx and ")" or ",)")
+
+    def sequence_visit(left, right):
+        def visit(self, node):
+            self.write(left)
+            for idx, item in enumerate(node.elts):
+                if idx:
+                    self.write(", ")
+                self.visit(item)
+            self.write(right)
+
+        return visit
+
+    visit_List = sequence_visit("[", "]")
+    visit_Set = sequence_visit("{", "}")
+    del sequence_visit
+
+    def visit_Dict(self, node):
+        self.write("{")
+        for idx, (key, value) in enumerate(zip(node.keys, node.values)):
+            if idx:
+                self.write(", ")
+            self.visit(key)
+            self.write(": ")
+            self.visit(value)
+        self.write("}")
+
+    def visit_BinOp(self, node):
+        self.write("(")
+        self.visit(node.left)
+        self.write(" %s " % BINOP_SYMBOLS[type(node.op)])
+        self.visit(node.right)
+        self.write(")")
+
+    def visit_BoolOp(self, node):
+        self.write("(")
+        for idx, value in enumerate(node.values):
+            if idx:
+                self.write(" %s " % BOOLOP_SYMBOLS[type(node.op)])
+            self.visit(value)
+        self.write(")")
+
+    def visit_Compare(self, node):
+        self.write("(")
+        self.visit(node.left)
+        for op, right in zip(node.ops, node.comparators):
+            self.write(" %s " % CMPOP_SYMBOLS[type(op)])
+            self.visit(right)
+        self.write(")")
+
+    def visit_UnaryOp(self, node):
+        self.write("(")
+        op = UNARYOP_SYMBOLS[type(node.op)]
+        self.write(op)
+        if op == "not":
+            self.write(" ")
+        self.visit(node.operand)
+        self.write(")")
+
+    def visit_Subscript(self, node):
+        self.visit(node.value)
+        self.write("[")
+        self.visit(node.slice)
+        self.write("]")
+
+    def visit_Slice(self, node):
+        if node.lower is not None:
+            self.visit(node.lower)
+        self.write(":")
+        if node.upper is not None:
+            self.visit(node.upper)
+        if node.step is not None:
+            self.write(":")
+            if not (isinstance(node.step, Name) and node.step.id == "None"):
+                self.visit(node.step)
+
+    def visit_ExtSlice(self, node):
+        for idx, item in node.dims:
+            if idx:
+                self.write(", ")
+            self.visit(item)
+
+    def visit_Yield(self, node):
+        self.write("yield ")
+        self.visit(node.value)
+
+    def visit_Lambda(self, node):
+        self.write("lambda ")
+        self.signature(node.args)
+        self.write(": ")
+        self.visit(node.body)
+
+    def visit_Ellipsis(self, node):
+        self.write("Ellipsis")
+
+    def generator_visit(left, right):
+        def visit(self, node):
+            self.write(left)
+            self.visit(node.elt)
+            for comprehension in node.generators:
+                self.visit(comprehension)
+            self.write(right)
+
+        return visit
+
+    visit_ListComp = generator_visit("[", "]")
+    visit_GeneratorExp = generator_visit("(", ")")
+    visit_SetComp = generator_visit("{", "}")
+    del generator_visit
+
+    def visit_DictComp(self, node):
+        self.write("{")
+        self.visit(node.key)
+        self.write(": ")
+        self.visit(node.value)
+        for comprehension in node.generators:
+            self.visit(comprehension)
+        self.write("}")
+
+    def visit_IfExp(self, node):
+        self.visit(node.body)
+        self.write(" if ")
+        self.visit(node.test)
+        self.write(" else ")
+        self.visit(node.orelse)
+
+    def visit_Starred(self, node):
+        self.write("*")
+        self.visit(node.value)
+
+    def visit_Repr(self, node):
+        # XXX: python 2.6 only
+        self.write("`")
+        self.visit(node.value)
+        self.write("`")
+
+    # Helper Nodes
+
+    def visit_alias(self, node):
+        self.write(node.name)
+        if node.asname is not None:
+            self.write(" as " + node.asname)
+
+    def visit_comprehension(self, node):
+        self.write(" for ")
+        self.visit(node.target)
+        self.write(" in ")
+        self.visit(node.iter)
+        if node.ifs:
+            for if_ in node.ifs:
+                self.write(" if ")
+                self.visit(if_)
+
+    def visit_excepthandler(self, node):
+        self.newline()
+        self.write("except")
+        if node.type is not None:
+            self.write(" ")
+            self.visit(node.type)
+            if node.name is not None:
+                self.write(" as ")
+                self.visit(node.name)
+        self.write(":")
+        self.body(node.body)
diff --git a/third_party/python/Mako/mako/ast.py b/third_party/python/Mako/mako/ast.py
new file mode 100644
index 0000000000..cfae28062c
--- /dev/null
+++ b/third_party/python/Mako/mako/ast.py
@@ -0,0 +1,205 @@
+# mako/ast.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""utilities for analyzing expressions and blocks of Python
+code, as well as generating Python from AST nodes"""
+
+import re
+
+from mako import compat
+from mako import exceptions
+from mako import pyparser
+
+
+class PythonCode(object):
+
+    """represents information about a string containing Python code"""
+
+    def __init__(self, code, **exception_kwargs):
+        self.code = code
+
+        # represents all identifiers which are assigned to at some point in
+        # the code
+        self.declared_identifiers = set()
+
+        # represents all identifiers which are referenced before their
+        # assignment, if any
+        self.undeclared_identifiers = set()
+
+        # note that an identifier can be in both the undeclared and declared
+        # lists.
+
+        # using AST to parse instead of using code.co_varnames,
+        # code.co_names has several advantages:
+        # - we can locate an identifier as "undeclared" even if
+        # its declared later in the same block of code
+        # - AST is less likely to break with version changes
+        # (for example, the behavior of co_names changed a little bit
+        # in python version 2.5)
+        if isinstance(code, compat.string_types):
+            expr = pyparser.parse(code.lstrip(), "exec", **exception_kwargs)
+        else:
+            expr = code
+
+        f = pyparser.FindIdentifiers(self, **exception_kwargs)
+        f.visit(expr)
+
+
+class ArgumentList(object):
+
+    """parses a fragment of code as a comma-separated list of expressions"""
+
+    def __init__(self, code, **exception_kwargs):
+        self.codeargs = []
+        self.args = []
+        self.declared_identifiers = set()
+        self.undeclared_identifiers = set()
+        if isinstance(code, compat.string_types):
+            if re.match(r"\S", code) and not re.match(r",\s*$", code):
+                # if theres text and no trailing comma, insure its parsed
+                # as a tuple by adding a trailing comma
+                code += ","
+            expr = pyparser.parse(code, "exec", **exception_kwargs)
+        else:
+            expr = code
+
+        f = pyparser.FindTuple(self, PythonCode, **exception_kwargs)
+        f.visit(expr)
+
+
+class PythonFragment(PythonCode):
+
+    """extends PythonCode to provide identifier lookups in partial control
+    statements
+
+    e.g.::
+
+        for x in 5:
+        elif y==9:
+        except (MyException, e):
+
+    """
+
+    def __init__(self, code, **exception_kwargs):
+        m = re.match(r"^(\w+)(?:\s+(.*?))?:\s*(#|$)", code.strip(), re.S)
+        if not m:
+            raise exceptions.CompileException(
+                "Fragment '%s' is not a partial control statement" % code,
+                **exception_kwargs
+            )
+        if m.group(3):
+            code = code[: m.start(3)]
+        (keyword, expr) = m.group(1, 2)
+        if keyword in ["for", "if", "while"]:
+            code = code + "pass"
+        elif keyword == "try":
+            code = code + "pass\nexcept:pass"
+        elif keyword == "elif" or keyword == "else":
+            code = "if False:pass\n" + code + "pass"
+        elif keyword == "except":
+            code = "try:pass\n" + code + "pass"
+        elif keyword == "with":
+            code = code + "pass"
+        else:
+            raise exceptions.CompileException(
+                "Unsupported control keyword: '%s'" % keyword,
+                **exception_kwargs
+            )
+        super(PythonFragment, self).__init__(code, **exception_kwargs)
+
+
+class FunctionDecl(object):
+
+    """function declaration"""
+
+    def __init__(self, code, allow_kwargs=True, **exception_kwargs):
+        self.code = code
+        expr = pyparser.parse(code, "exec", **exception_kwargs)
+
+        f = pyparser.ParseFunc(self, **exception_kwargs)
+        f.visit(expr)
+        if not hasattr(self, "funcname"):
+            raise exceptions.CompileException(
+                "Code '%s' is not a function declaration" % code,
+                **exception_kwargs
+            )
+        if not allow_kwargs and self.kwargs:
+            raise exceptions.CompileException(
+                "'**%s' keyword argument not allowed here"
+                % self.kwargnames[-1],
+                **exception_kwargs
+            )
+
+    def get_argument_expressions(self, as_call=False):
+        """Return the argument declarations of this FunctionDecl as a printable
+        list.
+
+        By default the return value is appropriate for writing in a ``def``;
+        set `as_call` to true to build arguments to be passed to the function
+        instead (assuming locals with the same names as the arguments exist).
+        """
+
+        namedecls = []
+
+        # Build in reverse order, since defaults and slurpy args come last
+        argnames = self.argnames[::-1]
+        kwargnames = self.kwargnames[::-1]
+        defaults = self.defaults[::-1]
+        kwdefaults = self.kwdefaults[::-1]
+
+        # Named arguments
+        if self.kwargs:
+            namedecls.append("**" + kwargnames.pop(0))
+
+        for name in kwargnames:
+            # Keyword-only arguments must always be used by name, so even if
+            # this is a call, print out `foo=foo`
+            if as_call:
+                namedecls.append("%s=%s" % (name, name))
+            elif kwdefaults:
+                default = kwdefaults.pop(0)
+                if default is None:
+                    # The AST always gives kwargs a default, since you can do
+                    # `def foo(*, a=1, b, c=3)`
+                    namedecls.append(name)
+                else:
+                    namedecls.append(
+                        "%s=%s"
+                        % (name, pyparser.ExpressionGenerator(default).value())
+                    )
+            else:
+                namedecls.append(name)
+
+        # Positional arguments
+        if self.varargs:
+            namedecls.append("*" + argnames.pop(0))
+
+        for name in argnames:
+            if as_call or not defaults:
+                namedecls.append(name)
+            else:
+                default = defaults.pop(0)
+                namedecls.append(
+                    "%s=%s"
+                    % (name, pyparser.ExpressionGenerator(default).value())
+                )
+
+        namedecls.reverse()
+        return namedecls
+
+    @property
+    def allargnames(self):
+        return tuple(self.argnames) + tuple(self.kwargnames)
+
+
+class FunctionArgs(FunctionDecl):
+
+    """the argument portion of a function declaration"""
+
+    def __init__(self, code, **kwargs):
+        super(FunctionArgs, self).__init__(
+            "def ANON(%s):pass" % code, **kwargs
+        )
diff --git a/third_party/python/Mako/mako/cache.py b/third_party/python/Mako/mako/cache.py
new file mode 100644
index 0000000000..26aa93ee38
--- /dev/null
+++ b/third_party/python/Mako/mako/cache.py
@@ -0,0 +1,240 @@
+# mako/cache.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+from mako import compat
+from mako import util
+
+_cache_plugins = util.PluginLoader("mako.cache")
+
+register_plugin = _cache_plugins.register
+register_plugin("beaker", "mako.ext.beaker_cache", "BeakerCacheImpl")
+
+
+class Cache(object):
+
+    """Represents a data content cache made available to the module
+    space of a specific :class:`.Template` object.
+
+    .. versionadded:: 0.6
+       :class:`.Cache` by itself is mostly a
+       container for a :class:`.CacheImpl` object, which implements
+       a fixed API to provide caching services; specific subclasses exist to
+       implement different
+       caching strategies.   Mako includes a backend that works with
+       the Beaker caching system.   Beaker itself then supports
+       a number of backends (i.e. file, memory, memcached, etc.)
+
+    The construction of a :class:`.Cache` is part of the mechanics
+    of a :class:`.Template`, and programmatic access to this
+    cache is typically via the :attr:`.Template.cache` attribute.
+
+    """
+
+    impl = None
+    """Provide the :class:`.CacheImpl` in use by this :class:`.Cache`.
+
+    This accessor allows a :class:`.CacheImpl` with additional
+    methods beyond that of :class:`.Cache` to be used programmatically.
+
+    """
+
+    id = None
+    """Return the 'id' that identifies this cache.
+
+    This is a value that should be globally unique to the
+    :class:`.Template` associated with this cache, and can
+    be used by a caching system to name a local container
+    for data specific to this template.
+
+    """
+
+    starttime = None
+    """Epochal time value for when the owning :class:`.Template` was
+    first compiled.
+
+    A cache implementation may wish to invalidate data earlier than
+    this timestamp; this has the effect of the cache for a specific
+    :class:`.Template` starting clean any time the :class:`.Template`
+    is recompiled, such as when the original template file changed on
+    the filesystem.
+
+    """
+
+    def __init__(self, template, *args):
+        # check for a stale template calling the
+        # constructor
+        if isinstance(template, compat.string_types) and args:
+            return
+        self.template = template
+        self.id = template.module.__name__
+        self.starttime = template.module._modified_time
+        self._def_regions = {}
+        self.impl = self._load_impl(self.template.cache_impl)
+
+    def _load_impl(self, name):
+        return _cache_plugins.load(name)(self)
+
+    def get_or_create(self, key, creation_function, **kw):
+        """Retrieve a value from the cache, using the given creation function
+        to generate a new value."""
+
+        return self._ctx_get_or_create(key, creation_function, None, **kw)
+
+    def _ctx_get_or_create(self, key, creation_function, context, **kw):
+        """Retrieve a value from the cache, using the given creation function
+        to generate a new value."""
+
+        if not self.template.cache_enabled:
+            return creation_function()
+
+        return self.impl.get_or_create(
+            key, creation_function, **self._get_cache_kw(kw, context)
+        )
+
+    def set(self, key, value, **kw):
+        r"""Place a value in the cache.
+
+        :param key: the value's key.
+        :param value: the value.
+        :param \**kw: cache configuration arguments.
+
+        """
+
+        self.impl.set(key, value, **self._get_cache_kw(kw, None))
+
+    put = set
+    """A synonym for :meth:`.Cache.set`.
+
+    This is here for backwards compatibility.
+
+    """
+
+    def get(self, key, **kw):
+        r"""Retrieve a value from the cache.
+
+        :param key: the value's key.
+        :param \**kw: cache configuration arguments.  The
+         backend is configured using these arguments upon first request.
+         Subsequent requests that use the same series of configuration
+         values will use that same backend.
+
+        """
+        return self.impl.get(key, **self._get_cache_kw(kw, None))
+
+    def invalidate(self, key, **kw):
+        r"""Invalidate a value in the cache.
+
+        :param key: the value's key.
+        :param \**kw: cache configuration arguments.  The
+         backend is configured using these arguments upon first request.
+         Subsequent requests that use the same series of configuration
+         values will use that same backend.
+
+        """
+        self.impl.invalidate(key, **self._get_cache_kw(kw, None))
+
+    def invalidate_body(self):
+        """Invalidate the cached content of the "body" method for this
+        template.
+
+        """
+        self.invalidate("render_body", __M_defname="render_body")
+
+    def invalidate_def(self, name):
+        """Invalidate the cached content of a particular ``<%def>`` within this
+        template.
+
+        """
+
+        self.invalidate("render_%s" % name, __M_defname="render_%s" % name)
+
+    def invalidate_closure(self, name):
+        """Invalidate a nested ``<%def>`` within this template.
+
+        Caching of nested defs is a blunt tool as there is no
+        management of scope -- nested defs that use cache tags
+        need to have names unique of all other nested defs in the
+        template, else their content will be overwritten by
+        each other.
+
+        """
+
+        self.invalidate(name, __M_defname=name)
+
+    def _get_cache_kw(self, kw, context):
+        defname = kw.pop("__M_defname", None)
+        if not defname:
+            tmpl_kw = self.template.cache_args.copy()
+            tmpl_kw.update(kw)
+        elif defname in self._def_regions:
+            tmpl_kw = self._def_regions[defname]
+        else:
+            tmpl_kw = self.template.cache_args.copy()
+            tmpl_kw.update(kw)
+            self._def_regions[defname] = tmpl_kw
+        if context and self.impl.pass_context:
+            tmpl_kw = tmpl_kw.copy()
+            tmpl_kw.setdefault("context", context)
+        return tmpl_kw
+
+
+class CacheImpl(object):
+
+    """Provide a cache implementation for use by :class:`.Cache`."""
+
+    def __init__(self, cache):
+        self.cache = cache
+
+    pass_context = False
+    """If ``True``, the :class:`.Context` will be passed to
+    :meth:`get_or_create <.CacheImpl.get_or_create>` as the name ``'context'``.
+    """
+
+    def get_or_create(self, key, creation_function, **kw):
+        r"""Retrieve a value from the cache, using the given creation function
+        to generate a new value.
+
+        This function *must* return a value, either from
+        the cache, or via the given creation function.
+        If the creation function is called, the newly
+        created value should be populated into the cache
+        under the given key before being returned.
+
+        :param key: the value's key.
+        :param creation_function: function that when called generates
+         a new value.
+        :param \**kw: cache configuration arguments.
+
+        """
+        raise NotImplementedError()
+
+    def set(self, key, value, **kw):
+        r"""Place a value in the cache.
+
+        :param key: the value's key.
+        :param value: the value.
+        :param \**kw: cache configuration arguments.
+
+        """
+        raise NotImplementedError()
+
+    def get(self, key, **kw):
+        r"""Retrieve a value from the cache.
+
+        :param key: the value's key.
+        :param \**kw: cache configuration arguments.
+
+        """
+        raise NotImplementedError()
+
+    def invalidate(self, key, **kw):
+        r"""Invalidate a value in the cache.
+
+        :param key: the value's key.
+        :param \**kw: cache configuration arguments.
+
+        """
+        raise NotImplementedError()
diff --git a/third_party/python/Mako/mako/cmd.py b/third_party/python/Mako/mako/cmd.py
new file mode 100644
index 0000000000..c0f2c754ec
--- /dev/null
+++ b/third_party/python/Mako/mako/cmd.py
@@ -0,0 +1,103 @@
+# mako/cmd.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+from argparse import ArgumentParser
+import io
+from os.path import dirname
+from os.path import isfile
+import sys
+
+from mako import exceptions
+from mako.lookup import TemplateLookup
+from mako.template import Template
+
+
+def varsplit(var):
+    if "=" not in var:
+        return (var, "")
+    return var.split("=", 1)
+
+
+def _exit():
+    sys.stderr.write(exceptions.text_error_template().render())
+    sys.exit(1)
+
+
+def cmdline(argv=None):
+
+    parser = ArgumentParser()
+    parser.add_argument(
+        "--var",
+        default=[],
+        action="append",
+        help="variable (can be used multiple times, use name=value)",
+    )
+    parser.add_argument(
+        "--template-dir",
+        default=[],
+        action="append",
+        help="Directory to use for template lookup (multiple "
+        "directories may be provided). If not given then if the "
+        "template is read from stdin, the value defaults to be "
+        "the current directory, otherwise it defaults to be the "
+        "parent directory of the file provided.",
+    )
+    parser.add_argument(
+        "--output-encoding", default=None, help="force output encoding"
+    )
+    parser.add_argument(
+        "--output-file",
+        default=None,
+        help="Write to file upon successful render instead of stdout",
+    )
+    parser.add_argument("input", nargs="?", default="-")
+
+    options = parser.parse_args(argv)
+
+    output_encoding = options.output_encoding
+    output_file = options.output_file
+
+    if options.input == "-":
+        lookup_dirs = options.template_dir or ["."]
+        lookup = TemplateLookup(lookup_dirs)
+        try:
+            template = Template(
+                sys.stdin.read(),
+                lookup=lookup,
+                output_encoding=output_encoding,
+            )
+        except:
+            _exit()
+    else:
+        filename = options.input
+        if not isfile(filename):
+            raise SystemExit("error: can't find %s" % filename)
+        lookup_dirs = options.template_dir or [dirname(filename)]
+        lookup = TemplateLookup(lookup_dirs)
+        try:
+            template = Template(
+                filename=filename,
+                lookup=lookup,
+                output_encoding=output_encoding,
+            )
+        except:
+            _exit()
+
+    kw = dict([varsplit(var) for var in options.var])
+    try:
+        rendered = template.render(**kw)
+    except:
+        _exit()
+    else:
+        if output_file:
+            io.open(output_file, "wt", encoding=output_encoding).write(
+                rendered
+            )
+        else:
+            sys.stdout.write(rendered)
+
+
+if __name__ == "__main__":
+    cmdline()
diff --git a/third_party/python/Mako/mako/codegen.py b/third_party/python/Mako/mako/codegen.py
new file mode 100644
index 0000000000..a9ae55b847
--- /dev/null
+++ b/third_party/python/Mako/mako/codegen.py
@@ -0,0 +1,1318 @@
+# mako/codegen.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""provides functionality for rendering a parsetree constructing into module
+source code."""
+
+import json
+import re
+import time
+
+from mako import ast
+from mako import compat
+from mako import exceptions
+from mako import filters
+from mako import parsetree
+from mako import util
+from mako.pygen import PythonPrinter
+
+
+MAGIC_NUMBER = 10
+
+# names which are hardwired into the
+# template and are not accessed via the
+# context itself
+TOPLEVEL_DECLARED = set(["UNDEFINED", "STOP_RENDERING"])
+RESERVED_NAMES = set(["context", "loop"]).union(TOPLEVEL_DECLARED)
+
+
+def compile(  # noqa
+    node,
+    uri,
+    filename=None,
+    default_filters=None,
+    buffer_filters=None,
+    imports=None,
+    future_imports=None,
+    source_encoding=None,
+    generate_magic_comment=True,
+    disable_unicode=False,
+    strict_undefined=False,
+    enable_loop=True,
+    reserved_names=frozenset(),
+):
+    """Generate module source code given a parsetree node,
+      uri, and optional source filename"""
+
+    # if on Py2K, push the "source_encoding" string to be
+    # a bytestring itself, as we will be embedding it into
+    # the generated source and we don't want to coerce the
+    # result into a unicode object, in "disable_unicode" mode
+    if not compat.py3k and isinstance(source_encoding, compat.text_type):
+        source_encoding = source_encoding.encode(source_encoding)
+
+    buf = util.FastEncodingBuffer()
+
+    printer = PythonPrinter(buf)
+    _GenerateRenderMethod(
+        printer,
+        _CompileContext(
+            uri,
+            filename,
+            default_filters,
+            buffer_filters,
+            imports,
+            future_imports,
+            source_encoding,
+            generate_magic_comment,
+            disable_unicode,
+            strict_undefined,
+            enable_loop,
+            reserved_names,
+        ),
+        node,
+    )
+    return buf.getvalue()
+
+
+class _CompileContext(object):
+    def __init__(
+        self,
+        uri,
+        filename,
+        default_filters,
+        buffer_filters,
+        imports,
+        future_imports,
+        source_encoding,
+        generate_magic_comment,
+        disable_unicode,
+        strict_undefined,
+        enable_loop,
+        reserved_names,
+    ):
+        self.uri = uri
+        self.filename = filename
+        self.default_filters = default_filters
+        self.buffer_filters = buffer_filters
+        self.imports = imports
+        self.future_imports = future_imports
+        self.source_encoding = source_encoding
+        self.generate_magic_comment = generate_magic_comment
+        self.disable_unicode = disable_unicode
+        self.strict_undefined = strict_undefined
+        self.enable_loop = enable_loop
+        self.reserved_names = reserved_names
+
+
+class _GenerateRenderMethod(object):
+
+    """A template visitor object which generates the
+       full module source for a template.
+
+    """
+
+    def __init__(self, printer, compiler, node):
+        self.printer = printer
+        self.compiler = compiler
+        self.node = node
+        self.identifier_stack = [None]
+        self.in_def = isinstance(node, (parsetree.DefTag, parsetree.BlockTag))
+
+        if self.in_def:
+            name = "render_%s" % node.funcname
+            args = node.get_argument_expressions()
+            filtered = len(node.filter_args.args) > 0
+            buffered = eval(node.attributes.get("buffered", "False"))
+            cached = eval(node.attributes.get("cached", "False"))
+            defs = None
+            pagetag = None
+            if node.is_block and not node.is_anonymous:
+                args += ["**pageargs"]
+        else:
+            defs = self.write_toplevel()
+            pagetag = self.compiler.pagetag
+            name = "render_body"
+            if pagetag is not None:
+                args = pagetag.body_decl.get_argument_expressions()
+                if not pagetag.body_decl.kwargs:
+                    args += ["**pageargs"]
+                cached = eval(pagetag.attributes.get("cached", "False"))
+                self.compiler.enable_loop = self.compiler.enable_loop or eval(
+                    pagetag.attributes.get("enable_loop", "False")
+                )
+            else:
+                args = ["**pageargs"]
+                cached = False
+            buffered = filtered = False
+        if args is None:
+            args = ["context"]
+        else:
+            args = [a for a in ["context"] + args]
+
+        self.write_render_callable(
+            pagetag or node, name, args, buffered, filtered, cached
+        )
+
+        if defs is not None:
+            for node in defs:
+                _GenerateRenderMethod(printer, compiler, node)
+
+        if not self.in_def:
+            self.write_metadata_struct()
+
+    def write_metadata_struct(self):
+        self.printer.source_map[self.printer.lineno] = max(
+            self.printer.source_map
+        )
+        struct = {
+            "filename": self.compiler.filename,
+            "uri": self.compiler.uri,
+            "source_encoding": self.compiler.source_encoding,
+            "line_map": self.printer.source_map,
+        }
+        self.printer.writelines(
+            '"""',
+            "__M_BEGIN_METADATA",
+            json.dumps(struct),
+            "__M_END_METADATA\n" '"""',
+        )
+
+    @property
+    def identifiers(self):
+        return self.identifier_stack[-1]
+
+    def write_toplevel(self):
+        """Traverse a template structure for module-level directives and
+        generate the start of module-level code.
+
+        """
+        inherit = []
+        namespaces = {}
+        module_code = []
+
+        self.compiler.pagetag = None
+
+        class FindTopLevel(object):
+            def visitInheritTag(s, node):
+                inherit.append(node)
+
+            def visitNamespaceTag(s, node):
+                namespaces[node.name] = node
+
+            def visitPageTag(s, node):
+                self.compiler.pagetag = node
+
+            def visitCode(s, node):
+                if node.ismodule:
+                    module_code.append(node)
+
+        f = FindTopLevel()
+        for n in self.node.nodes:
+            n.accept_visitor(f)
+
+        self.compiler.namespaces = namespaces
+
+        module_ident = set()
+        for n in module_code:
+            module_ident = module_ident.union(n.declared_identifiers())
+
+        module_identifiers = _Identifiers(self.compiler)
+        module_identifiers.declared = module_ident
+
+        # module-level names, python code
+        if (
+            self.compiler.generate_magic_comment
+            and self.compiler.source_encoding
+        ):
+            self.printer.writeline(
+                "# -*- coding:%s -*-" % self.compiler.source_encoding
+            )
+
+        if self.compiler.future_imports:
+            self.printer.writeline(
+                "from __future__ import %s"
+                % (", ".join(self.compiler.future_imports),)
+            )
+        self.printer.writeline("from mako import runtime, filters, cache")
+        self.printer.writeline("UNDEFINED = runtime.UNDEFINED")
+        self.printer.writeline("STOP_RENDERING = runtime.STOP_RENDERING")
+        self.printer.writeline("__M_dict_builtin = dict")
+        self.printer.writeline("__M_locals_builtin = locals")
+        self.printer.writeline("_magic_number = %r" % MAGIC_NUMBER)
+        self.printer.writeline("_modified_time = %r" % time.time())
+        self.printer.writeline("_enable_loop = %r" % self.compiler.enable_loop)
+        self.printer.writeline(
+            "_template_filename = %r" % self.compiler.filename
+        )
+        self.printer.writeline("_template_uri = %r" % self.compiler.uri)
+        self.printer.writeline(
+            "_source_encoding = %r" % self.compiler.source_encoding
+        )
+        if self.compiler.imports:
+            buf = ""
+            for imp in self.compiler.imports:
+                buf += imp + "\n"
+                self.printer.writeline(imp)
+            impcode = ast.PythonCode(
+                buf,
+                source="",
+                lineno=0,
+                pos=0,
+                filename="template defined imports",
+            )
+        else:
+            impcode = None
+
+        main_identifiers = module_identifiers.branch(self.node)
+        mit = module_identifiers.topleveldefs
+        module_identifiers.topleveldefs = mit.union(
+            main_identifiers.topleveldefs
+        )
+        module_identifiers.declared.update(TOPLEVEL_DECLARED)
+        if impcode:
+            module_identifiers.declared.update(impcode.declared_identifiers)
+
+        self.compiler.identifiers = module_identifiers
+        self.printer.writeline(
+            "_exports = %r"
+            % [n.name for n in main_identifiers.topleveldefs.values()]
+        )
+        self.printer.write_blanks(2)
+
+        if len(module_code):
+            self.write_module_code(module_code)
+
+        if len(inherit):
+            self.write_namespaces(namespaces)
+            self.write_inherit(inherit[-1])
+        elif len(namespaces):
+            self.write_namespaces(namespaces)
+
+        return list(main_identifiers.topleveldefs.values())
+
+    def write_render_callable(
+        self, node, name, args, buffered, filtered, cached
+    ):
+        """write a top-level render callable.
+
+        this could be the main render() method or that of a top-level def."""
+
+        if self.in_def:
+            decorator = node.decorator
+            if decorator:
+                self.printer.writeline(
+                    "@runtime._decorate_toplevel(%s)" % decorator
+                )
+
+        self.printer.start_source(node.lineno)
+        self.printer.writelines(
+            "def %s(%s):" % (name, ",".join(args)),
+            # push new frame, assign current frame to __M_caller
+            "__M_caller = context.caller_stack._push_frame()",
+            "try:",
+        )
+        if buffered or filtered or cached:
+            self.printer.writeline("context._push_buffer()")
+
+        self.identifier_stack.append(
+            self.compiler.identifiers.branch(self.node)
+        )
+        if (not self.in_def or self.node.is_block) and "**pageargs" in args:
+            self.identifier_stack[-1].argument_declared.add("pageargs")
+
+        if not self.in_def and (
+            len(self.identifiers.locally_assigned) > 0
+            or len(self.identifiers.argument_declared) > 0
+        ):
+            self.printer.writeline(
+                "__M_locals = __M_dict_builtin(%s)"
+                % ",".join(
+                    [
+                        "%s=%s" % (x, x)
+                        for x in self.identifiers.argument_declared
+                    ]
+                )
+            )
+
+        self.write_variable_declares(self.identifiers, toplevel=True)
+
+        for n in self.node.nodes:
+            n.accept_visitor(self)
+
+        self.write_def_finish(self.node, buffered, filtered, cached)
+        self.printer.writeline(None)
+        self.printer.write_blanks(2)
+        if cached:
+            self.write_cache_decorator(
+                node, name, args, buffered, self.identifiers, toplevel=True
+            )
+
+    def write_module_code(self, module_code):
+        """write module-level template code, i.e. that which
+        is enclosed in <%! %> tags in the template."""
+        for n in module_code:
+            self.printer.write_indented_block(n.text, starting_lineno=n.lineno)
+
+    def write_inherit(self, node):
+        """write the module-level inheritance-determination callable."""
+
+        self.printer.writelines(
+            "def _mako_inherit(template, context):",
+            "_mako_generate_namespaces(context)",
+            "return runtime._inherit_from(context, %s, _template_uri)"
+            % (node.parsed_attributes["file"]),
+            None,
+        )
+
+    def write_namespaces(self, namespaces):
+        """write the module-level namespace-generating callable."""
+        self.printer.writelines(
+            "def _mako_get_namespace(context, name):",
+            "try:",
+            "return context.namespaces[(__name__, name)]",
+            "except KeyError:",
+            "_mako_generate_namespaces(context)",
+            "return context.namespaces[(__name__, name)]",
+            None,
+            None,
+        )
+        self.printer.writeline("def _mako_generate_namespaces(context):")
+
+        for node in namespaces.values():
+            if "import" in node.attributes:
+                self.compiler.has_ns_imports = True
+            self.printer.start_source(node.lineno)
+            if len(node.nodes):
+                self.printer.writeline("def make_namespace():")
+                export = []
+                identifiers = self.compiler.identifiers.branch(node)
+                self.in_def = True
+
+                class NSDefVisitor(object):
+                    def visitDefTag(s, node):
+                        s.visitDefOrBase(node)
+
+                    def visitBlockTag(s, node):
+                        s.visitDefOrBase(node)
+
+                    def visitDefOrBase(s, node):
+                        if node.is_anonymous:
+                            raise exceptions.CompileException(
+                                "Can't put anonymous blocks inside "
+                                "<%namespace>",
+                                **node.exception_kwargs
+                            )
+                        self.write_inline_def(node, identifiers, nested=False)
+                        export.append(node.funcname)
+
+                vis = NSDefVisitor()
+                for n in node.nodes:
+                    n.accept_visitor(vis)
+                self.printer.writeline("return [%s]" % (",".join(export)))
+                self.printer.writeline(None)
+                self.in_def = False
+                callable_name = "make_namespace()"
+            else:
+                callable_name = "None"
+
+            if "file" in node.parsed_attributes:
+                self.printer.writeline(
+                    "ns = runtime.TemplateNamespace(%r,"
+                    " context._clean_inheritance_tokens(),"
+                    " templateuri=%s, callables=%s, "
+                    " calling_uri=_template_uri)"
+                    % (
+                        node.name,
+                        node.parsed_attributes.get("file", "None"),
+                        callable_name,
+                    )
+                )
+            elif "module" in node.parsed_attributes:
+                self.printer.writeline(
+                    "ns = runtime.ModuleNamespace(%r,"
+                    " context._clean_inheritance_tokens(),"
+                    " callables=%s, calling_uri=_template_uri,"
+                    " module=%s)"
+                    % (
+                        node.name,
+                        callable_name,
+                        node.parsed_attributes.get("module", "None"),
+                    )
+                )
+            else:
+                self.printer.writeline(
+                    "ns = runtime.Namespace(%r,"
+                    " context._clean_inheritance_tokens(),"
+                    " callables=%s, calling_uri=_template_uri)"
+                    % (node.name, callable_name)
+                )
+            if eval(node.attributes.get("inheritable", "False")):
+                self.printer.writeline("context['self'].%s = ns" % (node.name))
+
+            self.printer.writeline(
+                "context.namespaces[(__name__, %s)] = ns" % repr(node.name)
+            )
+            self.printer.write_blanks(1)
+        if not len(namespaces):
+            self.printer.writeline("pass")
+        self.printer.writeline(None)
+
+    def write_variable_declares(self, identifiers, toplevel=False, limit=None):
+        """write variable declarations at the top of a function.
+
+        the variable declarations are in the form of callable
+        definitions for defs and/or name lookup within the
+        function's context argument. the names declared are based
+        on the names that are referenced in the function body,
+        which don't otherwise have any explicit assignment
+        operation. names that are assigned within the body are
+        assumed to be locally-scoped variables and are not
+        separately declared.
+
+        for def callable definitions, if the def is a top-level
+        callable then a 'stub' callable is generated which wraps
+        the current Context into a closure. if the def is not
+        top-level, it is fully rendered as a local closure.
+
+        """
+
+        # collection of all defs available to us in this scope
+        comp_idents = dict([(c.funcname, c) for c in identifiers.defs])
+        to_write = set()
+
+        # write "context.get()" for all variables we are going to
+        # need that arent in the namespace yet
+        to_write = to_write.union(identifiers.undeclared)
+
+        # write closure functions for closures that we define
+        # right here
+        to_write = to_write.union(
+            [c.funcname for c in identifiers.closuredefs.values()]
+        )
+
+        # remove identifiers that are declared in the argument
+        # signature of the callable
+        to_write = to_write.difference(identifiers.argument_declared)
+
+        # remove identifiers that we are going to assign to.
+        # in this way we mimic Python's behavior,
+        # i.e. assignment to a variable within a block
+        # means that variable is now a "locally declared" var,
+        # which cannot be referenced beforehand.
+        to_write = to_write.difference(identifiers.locally_declared)
+
+        if self.compiler.enable_loop:
+            has_loop = "loop" in to_write
+            to_write.discard("loop")
+        else:
+            has_loop = False
+
+        # if a limiting set was sent, constraint to those items in that list
+        # (this is used for the caching decorator)
+        if limit is not None:
+            to_write = to_write.intersection(limit)
+
+        if toplevel and getattr(self.compiler, "has_ns_imports", False):
+            self.printer.writeline("_import_ns = {}")
+            self.compiler.has_imports = True
+            for ident, ns in self.compiler.namespaces.items():
+                if "import" in ns.attributes:
+                    self.printer.writeline(
+                        "_mako_get_namespace(context, %r)."
+                        "_populate(_import_ns, %r)"
+                        % (
+                            ident,
+                            re.split(r"\s*,\s*", ns.attributes["import"]),
+                        )
+                    )
+
+        if has_loop:
+            self.printer.writeline("loop = __M_loop = runtime.LoopStack()")
+
+        for ident in to_write:
+            if ident in comp_idents:
+                comp = comp_idents[ident]
+                if comp.is_block:
+                    if not comp.is_anonymous:
+                        self.write_def_decl(comp, identifiers)
+                    else:
+                        self.write_inline_def(comp, identifiers, nested=True)
+                else:
+                    if comp.is_root():
+                        self.write_def_decl(comp, identifiers)
+                    else:
+                        self.write_inline_def(comp, identifiers, nested=True)
+
+            elif ident in self.compiler.namespaces:
+                self.printer.writeline(
+                    "%s = _mako_get_namespace(context, %r)" % (ident, ident)
+                )
+            else:
+                if getattr(self.compiler, "has_ns_imports", False):
+                    if self.compiler.strict_undefined:
+                        self.printer.writelines(
+                            "%s = _import_ns.get(%r, UNDEFINED)"
+                            % (ident, ident),
+                            "if %s is UNDEFINED:" % ident,
+                            "try:",
+                            "%s = context[%r]" % (ident, ident),
+                            "except KeyError:",
+                            "raise NameError(\"'%s' is not defined\")" % ident,
+                            None,
+                            None,
+                        )
+                    else:
+                        self.printer.writeline(
+                            "%s = _import_ns.get"
+                            "(%r, context.get(%r, UNDEFINED))"
+                            % (ident, ident, ident)
+                        )
+                else:
+                    if self.compiler.strict_undefined:
+                        self.printer.writelines(
+                            "try:",
+                            "%s = context[%r]" % (ident, ident),
+                            "except KeyError:",
+                            "raise NameError(\"'%s' is not defined\")" % ident,
+                            None,
+                        )
+                    else:
+                        self.printer.writeline(
+                            "%s = context.get(%r, UNDEFINED)" % (ident, ident)
+                        )
+
+        self.printer.writeline("__M_writer = context.writer()")
+
+    def write_def_decl(self, node, identifiers):
+        """write a locally-available callable referencing a top-level def"""
+        funcname = node.funcname
+        namedecls = node.get_argument_expressions()
+        nameargs = node.get_argument_expressions(as_call=True)
+
+        if not self.in_def and (
+            len(self.identifiers.locally_assigned) > 0
+            or len(self.identifiers.argument_declared) > 0
+        ):
+            nameargs.insert(0, "context._locals(__M_locals)")
+        else:
+            nameargs.insert(0, "context")
+        self.printer.writeline("def %s(%s):" % (funcname, ",".join(namedecls)))
+        self.printer.writeline(
+            "return render_%s(%s)" % (funcname, ",".join(nameargs))
+        )
+        self.printer.writeline(None)
+
+    def write_inline_def(self, node, identifiers, nested):
+        """write a locally-available def callable inside an enclosing def."""
+
+        namedecls = node.get_argument_expressions()
+
+        decorator = node.decorator
+        if decorator:
+            self.printer.writeline(
+                "@runtime._decorate_inline(context, %s)" % decorator
+            )
+        self.printer.writeline(
+            "def %s(%s):" % (node.funcname, ",".join(namedecls))
+        )
+        filtered = len(node.filter_args.args) > 0
+        buffered = eval(node.attributes.get("buffered", "False"))
+        cached = eval(node.attributes.get("cached", "False"))
+        self.printer.writelines(
+            # push new frame, assign current frame to __M_caller
+            "__M_caller = context.caller_stack._push_frame()",
+            "try:",
+        )
+        if buffered or filtered or cached:
+            self.printer.writelines("context._push_buffer()")
+
+        identifiers = identifiers.branch(node, nested=nested)
+
+        self.write_variable_declares(identifiers)
+
+        self.identifier_stack.append(identifiers)
+        for n in node.nodes:
+            n.accept_visitor(self)
+        self.identifier_stack.pop()
+
+        self.write_def_finish(node, buffered, filtered, cached)
+        self.printer.writeline(None)
+        if cached:
+            self.write_cache_decorator(
+                node,
+                node.funcname,
+                namedecls,
+                False,
+                identifiers,
+                inline=True,
+                toplevel=False,
+            )
+
+    def write_def_finish(
+        self, node, buffered, filtered, cached, callstack=True
+    ):
+        """write the end section of a rendering function, either outermost or
+        inline.
+
+        this takes into account if the rendering function was filtered,
+        buffered, etc.  and closes the corresponding try: block if any, and
+        writes code to retrieve captured content, apply filters, send proper
+        return value."""
+
+        if not buffered and not cached and not filtered:
+            self.printer.writeline("return ''")
+            if callstack:
+                self.printer.writelines(
+                    "finally:", "context.caller_stack._pop_frame()", None
+                )
+
+        if buffered or filtered or cached:
+            if buffered or cached:
+                # in a caching scenario, don't try to get a writer
+                # from the context after popping; assume the caching
+                # implemenation might be using a context with no
+                # extra buffers
+                self.printer.writelines(
+                    "finally:", "__M_buf = context._pop_buffer()"
+                )
+            else:
+                self.printer.writelines(
+                    "finally:",
+                    "__M_buf, __M_writer = context._pop_buffer_and_writer()",
+                )
+
+            if callstack:
+                self.printer.writeline("context.caller_stack._pop_frame()")
+
+            s = "__M_buf.getvalue()"
+            if filtered:
+                s = self.create_filter_callable(
+                    node.filter_args.args, s, False
+                )
+            self.printer.writeline(None)
+            if buffered and not cached:
+                s = self.create_filter_callable(
+                    self.compiler.buffer_filters, s, False
+                )
+            if buffered or cached:
+                self.printer.writeline("return %s" % s)
+            else:
+                self.printer.writelines("__M_writer(%s)" % s, "return ''")
+
+    def write_cache_decorator(
+        self,
+        node_or_pagetag,
+        name,
+        args,
+        buffered,
+        identifiers,
+        inline=False,
+        toplevel=False,
+    ):
+        """write a post-function decorator to replace a rendering
+            callable with a cached version of itself."""
+
+        self.printer.writeline("__M_%s = %s" % (name, name))
+        cachekey = node_or_pagetag.parsed_attributes.get(
+            "cache_key", repr(name)
+        )
+
+        cache_args = {}
+        if self.compiler.pagetag is not None:
+            cache_args.update(
+                (pa[6:], self.compiler.pagetag.parsed_attributes[pa])
+                for pa in self.compiler.pagetag.parsed_attributes
+                if pa.startswith("cache_") and pa != "cache_key"
+            )
+        cache_args.update(
+            (pa[6:], node_or_pagetag.parsed_attributes[pa])
+            for pa in node_or_pagetag.parsed_attributes
+            if pa.startswith("cache_") and pa != "cache_key"
+        )
+        if "timeout" in cache_args:
+            cache_args["timeout"] = int(eval(cache_args["timeout"]))
+
+        self.printer.writeline("def %s(%s):" % (name, ",".join(args)))
+
+        # form "arg1, arg2, arg3=arg3, arg4=arg4", etc.
+        pass_args = [
+            "%s=%s" % ((a.split("=")[0],) * 2) if "=" in a else a for a in args
+        ]
+
+        self.write_variable_declares(
+            identifiers,
+            toplevel=toplevel,
+            limit=node_or_pagetag.undeclared_identifiers(),
+        )
+        if buffered:
+            s = (
+                "context.get('local')."
+                "cache._ctx_get_or_create("
+                "%s, lambda:__M_%s(%s),  context, %s__M_defname=%r)"
+                % (
+                    cachekey,
+                    name,
+                    ",".join(pass_args),
+                    "".join(
+                        ["%s=%s, " % (k, v) for k, v in cache_args.items()]
+                    ),
+                    name,
+                )
+            )
+            # apply buffer_filters
+            s = self.create_filter_callable(
+                self.compiler.buffer_filters, s, False
+            )
+            self.printer.writelines("return " + s, None)
+        else:
+            self.printer.writelines(
+                "__M_writer(context.get('local')."
+                "cache._ctx_get_or_create("
+                "%s, lambda:__M_%s(%s), context, %s__M_defname=%r))"
+                % (
+                    cachekey,
+                    name,
+                    ",".join(pass_args),
+                    "".join(
+                        ["%s=%s, " % (k, v) for k, v in cache_args.items()]
+                    ),
+                    name,
+                ),
+                "return ''",
+                None,
+            )
+
+    def create_filter_callable(self, args, target, is_expression):
+        """write a filter-applying expression based on the filters
+        present in the given filter names, adjusting for the global
+        'default' filter aliases as needed."""
+
+        def locate_encode(name):
+            if re.match(r"decode\..+", name):
+                return "filters." + name
+            elif self.compiler.disable_unicode:
+                return filters.NON_UNICODE_ESCAPES.get(name, name)
+            else:
+                return filters.DEFAULT_ESCAPES.get(name, name)
+
+        if "n" not in args:
+            if is_expression:
+                if self.compiler.pagetag:
+                    args = self.compiler.pagetag.filter_args.args + args
+                if self.compiler.default_filters and "n" not in args:
+                    args = self.compiler.default_filters + args
+        for e in args:
+            # if filter given as a function, get just the identifier portion
+            if e == "n":
+                continue
+            m = re.match(r"(.+?)(\(.*\))", e)
+            if m:
+                ident, fargs = m.group(1, 2)
+                f = locate_encode(ident)
+                e = f + fargs
+            else:
+                e = locate_encode(e)
+                assert e is not None
+            target = "%s(%s)" % (e, target)
+        return target
+
+    def visitExpression(self, node):
+        self.printer.start_source(node.lineno)
+        if (
+            len(node.escapes)
+            or (
+                self.compiler.pagetag is not None
+                and len(self.compiler.pagetag.filter_args.args)
+            )
+            or len(self.compiler.default_filters)
+        ):
+
+            s = self.create_filter_callable(
+                node.escapes_code.args, "%s" % node.text, True
+            )
+            self.printer.writeline("__M_writer(%s)" % s)
+        else:
+            self.printer.writeline("__M_writer(%s)" % node.text)
+
+    def visitControlLine(self, node):
+        if node.isend:
+            self.printer.writeline(None)
+            if node.has_loop_context:
+                self.printer.writeline("finally:")
+                self.printer.writeline("loop = __M_loop._exit()")
+                self.printer.writeline(None)
+        else:
+            self.printer.start_source(node.lineno)
+            if self.compiler.enable_loop and node.keyword == "for":
+                text = mangle_mako_loop(node, self.printer)
+            else:
+                text = node.text
+            self.printer.writeline(text)
+            children = node.get_children()
+            # this covers the three situations where we want to insert a pass:
+            #    1) a ternary control line with no children,
+            #    2) a primary control line with nothing but its own ternary
+            #          and end control lines, and
+            #    3) any control line with no content other than comments
+            if not children or (
+                compat.all(
+                    isinstance(c, (parsetree.Comment, parsetree.ControlLine))
+                    for c in children
+                )
+                and compat.all(
+                    (node.is_ternary(c.keyword) or c.isend)
+                    for c in children
+                    if isinstance(c, parsetree.ControlLine)
+                )
+            ):
+                self.printer.writeline("pass")
+
+    def visitText(self, node):
+        self.printer.start_source(node.lineno)
+        self.printer.writeline("__M_writer(%s)" % repr(node.content))
+
+    def visitTextTag(self, node):
+        filtered = len(node.filter_args.args) > 0
+        if filtered:
+            self.printer.writelines(
+                "__M_writer = context._push_writer()", "try:"
+            )
+        for n in node.nodes:
+            n.accept_visitor(self)
+        if filtered:
+            self.printer.writelines(
+                "finally:",
+                "__M_buf, __M_writer = context._pop_buffer_and_writer()",
+                "__M_writer(%s)"
+                % self.create_filter_callable(
+                    node.filter_args.args, "__M_buf.getvalue()", False
+                ),
+                None,
+            )
+
+    def visitCode(self, node):
+        if not node.ismodule:
+            self.printer.write_indented_block(
+                node.text, starting_lineno=node.lineno
+            )
+
+            if not self.in_def and len(self.identifiers.locally_assigned) > 0:
+                # if we are the "template" def, fudge locally
+                # declared/modified variables into the "__M_locals" dictionary,
+                # which is used for def calls within the same template,
+                # to simulate "enclosing scope"
+                self.printer.writeline(
+                    "__M_locals_builtin_stored = __M_locals_builtin()"
+                )
+                self.printer.writeline(
+                    "__M_locals.update(__M_dict_builtin([(__M_key,"
+                    " __M_locals_builtin_stored[__M_key]) for __M_key in"
+                    " [%s] if __M_key in __M_locals_builtin_stored]))"
+                    % ",".join([repr(x) for x in node.declared_identifiers()])
+                )
+
+    def visitIncludeTag(self, node):
+        self.printer.start_source(node.lineno)
+        args = node.attributes.get("args")
+        if args:
+            self.printer.writeline(
+                "runtime._include_file(context, %s, _template_uri, %s)"
+                % (node.parsed_attributes["file"], args)
+            )
+        else:
+            self.printer.writeline(
+                "runtime._include_file(context, %s, _template_uri)"
+                % (node.parsed_attributes["file"])
+            )
+
+    def visitNamespaceTag(self, node):
+        pass
+
+    def visitDefTag(self, node):
+        pass
+
+    def visitBlockTag(self, node):
+        if node.is_anonymous:
+            self.printer.writeline("%s()" % node.funcname)
+        else:
+            nameargs = node.get_argument_expressions(as_call=True)
+            nameargs += ["**pageargs"]
+            self.printer.writeline(
+                "if 'parent' not in context._data or "
+                "not hasattr(context._data['parent'], '%s'):" % node.funcname
+            )
+            self.printer.writeline(
+                "context['self'].%s(%s)" % (node.funcname, ",".join(nameargs))
+            )
+            self.printer.writeline("\n")
+
+    def visitCallNamespaceTag(self, node):
+        # TODO: we can put namespace-specific checks here, such
+        # as ensure the given namespace will be imported,
+        # pre-import the namespace, etc.
+        self.visitCallTag(node)
+
+    def visitCallTag(self, node):
+        self.printer.writeline("def ccall(caller):")
+        export = ["body"]
+        callable_identifiers = self.identifiers.branch(node, nested=True)
+        body_identifiers = callable_identifiers.branch(node, nested=False)
+        # we want the 'caller' passed to ccall to be used
+        # for the body() function, but for other non-body()
+        # <%def>s within <%call> we want the current caller
+        # off the call stack (if any)
+        body_identifiers.add_declared("caller")
+
+        self.identifier_stack.append(body_identifiers)
+
+        class DefVisitor(object):
+            def visitDefTag(s, node):
+                s.visitDefOrBase(node)
+
+            def visitBlockTag(s, node):
+                s.visitDefOrBase(node)
+
+            def visitDefOrBase(s, node):
+                self.write_inline_def(node, callable_identifiers, nested=False)
+                if not node.is_anonymous:
+                    export.append(node.funcname)
+                # remove defs that are within the <%call> from the
+                # "closuredefs" defined in the body, so they dont render twice
+                if node.funcname in body_identifiers.closuredefs:
+                    del body_identifiers.closuredefs[node.funcname]
+
+        vis = DefVisitor()
+        for n in node.nodes:
+            n.accept_visitor(vis)
+        self.identifier_stack.pop()
+
+        bodyargs = node.body_decl.get_argument_expressions()
+        self.printer.writeline("def body(%s):" % ",".join(bodyargs))
+
+        # TODO: figure out best way to specify
+        # buffering/nonbuffering (at call time would be better)
+        buffered = False
+        if buffered:
+            self.printer.writelines("context._push_buffer()", "try:")
+        self.write_variable_declares(body_identifiers)
+        self.identifier_stack.append(body_identifiers)
+
+        for n in node.nodes:
+            n.accept_visitor(self)
+        self.identifier_stack.pop()
+
+        self.write_def_finish(node, buffered, False, False, callstack=False)
+        self.printer.writelines(None, "return [%s]" % (",".join(export)), None)
+
+        self.printer.writelines(
+            # push on caller for nested call
+            "context.caller_stack.nextcaller = "
+            "runtime.Namespace('caller', context, "
+            "callables=ccall(__M_caller))",
+            "try:",
+        )
+        self.printer.start_source(node.lineno)
+        self.printer.writelines(
+            "__M_writer(%s)"
+            % self.create_filter_callable([], node.expression, True),
+            "finally:",
+            "context.caller_stack.nextcaller = None",
+            None,
+        )
+
+
+class _Identifiers(object):
+
+    """tracks the status of identifier names as template code is rendered."""
+
+    def __init__(self, compiler, node=None, parent=None, nested=False):
+        if parent is not None:
+            # if we are the branch created in write_namespaces(),
+            # we don't share any context from the main body().
+            if isinstance(node, parsetree.NamespaceTag):
+                self.declared = set()
+                self.topleveldefs = util.SetLikeDict()
+            else:
+                # things that have already been declared
+                # in an enclosing namespace (i.e. names we can just use)
+                self.declared = (
+                    set(parent.declared)
+                    .union([c.name for c in parent.closuredefs.values()])
+                    .union(parent.locally_declared)
+                    .union(parent.argument_declared)
+                )
+
+                # if these identifiers correspond to a "nested"
+                # scope, it means whatever the parent identifiers
+                # had as undeclared will have been declared by that parent,
+                # and therefore we have them in our scope.
+                if nested:
+                    self.declared = self.declared.union(parent.undeclared)
+
+                # top level defs that are available
+                self.topleveldefs = util.SetLikeDict(**parent.topleveldefs)
+        else:
+            self.declared = set()
+            self.topleveldefs = util.SetLikeDict()
+
+        self.compiler = compiler
+
+        # things within this level that are referenced before they
+        # are declared (e.g. assigned to)
+        self.undeclared = set()
+
+        # things that are declared locally.  some of these things
+        # could be in the "undeclared" list as well if they are
+        # referenced before declared
+        self.locally_declared = set()
+
+        # assignments made in explicit python blocks.
+        # these will be propagated to
+        # the context of local def calls.
+        self.locally_assigned = set()
+
+        # things that are declared in the argument
+        # signature of the def callable
+        self.argument_declared = set()
+
+        # closure defs that are defined in this level
+        self.closuredefs = util.SetLikeDict()
+
+        self.node = node
+
+        if node is not None:
+            node.accept_visitor(self)
+
+        illegal_names = self.compiler.reserved_names.intersection(
+            self.locally_declared
+        )
+        if illegal_names:
+            raise exceptions.NameConflictError(
+                "Reserved words declared in template: %s"
+                % ", ".join(illegal_names)
+            )
+
+    def branch(self, node, **kwargs):
+        """create a new Identifiers for a new Node, with
+          this Identifiers as the parent."""
+
+        return _Identifiers(self.compiler, node, self, **kwargs)
+
+    @property
+    def defs(self):
+        return set(self.topleveldefs.union(self.closuredefs).values())
+
+    def __repr__(self):
+        return (
+            "Identifiers(declared=%r, locally_declared=%r, "
+            "undeclared=%r, topleveldefs=%r, closuredefs=%r, "
+            "argumentdeclared=%r)"
+            % (
+                list(self.declared),
+                list(self.locally_declared),
+                list(self.undeclared),
+                [c.name for c in self.topleveldefs.values()],
+                [c.name for c in self.closuredefs.values()],
+                self.argument_declared,
+            )
+        )
+
+    def check_declared(self, node):
+        """update the state of this Identifiers with the undeclared
+            and declared identifiers of the given node."""
+
+        for ident in node.undeclared_identifiers():
+            if ident != "context" and ident not in self.declared.union(
+                self.locally_declared
+            ):
+                self.undeclared.add(ident)
+        for ident in node.declared_identifiers():
+            self.locally_declared.add(ident)
+
+    def add_declared(self, ident):
+        self.declared.add(ident)
+        if ident in self.undeclared:
+            self.undeclared.remove(ident)
+
+    def visitExpression(self, node):
+        self.check_declared(node)
+
+    def visitControlLine(self, node):
+        self.check_declared(node)
+
+    def visitCode(self, node):
+        if not node.ismodule:
+            self.check_declared(node)
+            self.locally_assigned = self.locally_assigned.union(
+                node.declared_identifiers()
+            )
+
+    def visitNamespaceTag(self, node):
+        # only traverse into the sub-elements of a
+        # <%namespace> tag if we are the branch created in
+        # write_namespaces()
+        if self.node is node:
+            for n in node.nodes:
+                n.accept_visitor(self)
+
+    def _check_name_exists(self, collection, node):
+        existing = collection.get(node.funcname)
+        collection[node.funcname] = node
+        if (
+            existing is not None
+            and existing is not node
+            and (node.is_block or existing.is_block)
+        ):
+            raise exceptions.CompileException(
+                "%%def or %%block named '%s' already "
+                "exists in this template." % node.funcname,
+                **node.exception_kwargs
+            )
+
+    def visitDefTag(self, node):
+        if node.is_root() and not node.is_anonymous:
+            self._check_name_exists(self.topleveldefs, node)
+        elif node is not self.node:
+            self._check_name_exists(self.closuredefs, node)
+
+        for ident in node.undeclared_identifiers():
+            if ident != "context" and ident not in self.declared.union(
+                self.locally_declared
+            ):
+                self.undeclared.add(ident)
+
+        # visit defs only one level deep
+        if node is self.node:
+            for ident in node.declared_identifiers():
+                self.argument_declared.add(ident)
+
+            for n in node.nodes:
+                n.accept_visitor(self)
+
+    def visitBlockTag(self, node):
+        if node is not self.node and not node.is_anonymous:
+
+            if isinstance(self.node, parsetree.DefTag):
+                raise exceptions.CompileException(
+                    "Named block '%s' not allowed inside of def '%s'"
+                    % (node.name, self.node.name),
+                    **node.exception_kwargs
+                )
+            elif isinstance(
+                self.node, (parsetree.CallTag, parsetree.CallNamespaceTag)
+            ):
+                raise exceptions.CompileException(
+                    "Named block '%s' not allowed inside of <%%call> tag"
+                    % (node.name,),
+                    **node.exception_kwargs
+                )
+
+        for ident in node.undeclared_identifiers():
+            if ident != "context" and ident not in self.declared.union(
+                self.locally_declared
+            ):
+                self.undeclared.add(ident)
+
+        if not node.is_anonymous:
+            self._check_name_exists(self.topleveldefs, node)
+            self.undeclared.add(node.funcname)
+        elif node is not self.node:
+            self._check_name_exists(self.closuredefs, node)
+        for ident in node.declared_identifiers():
+            self.argument_declared.add(ident)
+        for n in node.nodes:
+            n.accept_visitor(self)
+
+    def visitTextTag(self, node):
+        for ident in node.undeclared_identifiers():
+            if ident != "context" and ident not in self.declared.union(
+                self.locally_declared
+            ):
+                self.undeclared.add(ident)
+
+    def visitIncludeTag(self, node):
+        self.check_declared(node)
+
+    def visitPageTag(self, node):
+        for ident in node.declared_identifiers():
+            self.argument_declared.add(ident)
+        self.check_declared(node)
+
+    def visitCallNamespaceTag(self, node):
+        self.visitCallTag(node)
+
+    def visitCallTag(self, node):
+        if node is self.node:
+            for ident in node.undeclared_identifiers():
+                if ident != "context" and ident not in self.declared.union(
+                    self.locally_declared
+                ):
+                    self.undeclared.add(ident)
+            for ident in node.declared_identifiers():
+                self.argument_declared.add(ident)
+            for n in node.nodes:
+                n.accept_visitor(self)
+        else:
+            for ident in node.undeclared_identifiers():
+                if ident != "context" and ident not in self.declared.union(
+                    self.locally_declared
+                ):
+                    self.undeclared.add(ident)
+
+
+_FOR_LOOP = re.compile(
+    r"^for\s+((?:\(?)\s*[A-Za-z_][A-Za-z_0-9]*"
+    r"(?:\s*,\s*(?:[A-Za-z_][A-Za-z0-9_]*),??)*\s*(?:\)?))\s+in\s+(.*):"
+)
+
+
+def mangle_mako_loop(node, printer):
+    """converts a for loop into a context manager wrapped around a for loop
+    when access to the `loop` variable has been detected in the for loop body
+    """
+    loop_variable = LoopVariable()
+    node.accept_visitor(loop_variable)
+    if loop_variable.detected:
+        node.nodes[-1].has_loop_context = True
+        match = _FOR_LOOP.match(node.text)
+        if match:
+            printer.writelines(
+                "loop = __M_loop._enter(%s)" % match.group(2),
+                "try:"
+                # 'with __M_loop(%s) as loop:' % match.group(2)
+            )
+            text = "for %s in loop:" % match.group(1)
+        else:
+            raise SyntaxError("Couldn't apply loop context: %s" % node.text)
+    else:
+        text = node.text
+    return text
+
+
+class LoopVariable(object):
+
+    """A node visitor which looks for the name 'loop' within undeclared
+    identifiers."""
+
+    def __init__(self):
+        self.detected = False
+
+    def _loop_reference_detected(self, node):
+        if "loop" in node.undeclared_identifiers():
+            self.detected = True
+        else:
+            for n in node.get_children():
+                n.accept_visitor(self)
+
+    def visitControlLine(self, node):
+        self._loop_reference_detected(node)
+
+    def visitCode(self, node):
+        self._loop_reference_detected(node)
+
+    def visitExpression(self, node):
+        self._loop_reference_detected(node)
diff --git a/third_party/python/Mako/mako/compat.py b/third_party/python/Mako/mako/compat.py
new file mode 100644
index 0000000000..9aac98cb5b
--- /dev/null
+++ b/third_party/python/Mako/mako/compat.py
@@ -0,0 +1,166 @@
+# mako/compat.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+import collections
+import inspect
+import sys
+
+py3k = sys.version_info >= (3, 0)
+py2k = sys.version_info < (3,)
+py27 = sys.version_info >= (2, 7)
+jython = sys.platform.startswith("java")
+win32 = sys.platform.startswith("win")
+pypy = hasattr(sys, "pypy_version_info")
+
+ArgSpec = collections.namedtuple(
+    "ArgSpec", ["args", "varargs", "keywords", "defaults"]
+)
+
+
+def inspect_getargspec(func):
+    """getargspec based on fully vendored getfullargspec from Python 3.3."""
+
+    if inspect.ismethod(func):
+        func = func.__func__
+    if not inspect.isfunction(func):
+        raise TypeError("{!r} is not a Python function".format(func))
+
+    co = func.__code__
+    if not inspect.iscode(co):
+        raise TypeError("{!r} is not a code object".format(co))
+
+    nargs = co.co_argcount
+    names = co.co_varnames
+    nkwargs = co.co_kwonlyargcount if py3k else 0
+    args = list(names[:nargs])
+
+    nargs += nkwargs
+    varargs = None
+    if co.co_flags & inspect.CO_VARARGS:
+        varargs = co.co_varnames[nargs]
+        nargs = nargs + 1
+    varkw = None
+    if co.co_flags & inspect.CO_VARKEYWORDS:
+        varkw = co.co_varnames[nargs]
+
+    return ArgSpec(args, varargs, varkw, func.__defaults__)
+
+
+if py3k:
+    from io import StringIO
+    import builtins as compat_builtins
+    from urllib.parse import quote_plus, unquote_plus
+    from html.entities import codepoint2name, name2codepoint
+
+    string_types = (str,)
+    binary_type = bytes
+    text_type = str
+
+    from io import BytesIO as byte_buffer
+
+    def u(s):
+        return s
+
+    def b(s):
+        return s.encode("latin-1")
+
+    def octal(lit):
+        return eval("0o" + lit)
+
+
+else:
+    import __builtin__ as compat_builtins  # noqa
+
+    try:
+        from cStringIO import StringIO
+    except:
+        from StringIO import StringIO
+
+    byte_buffer = StringIO
+
+    from urllib import quote_plus, unquote_plus  # noqa
+    from htmlentitydefs import codepoint2name, name2codepoint  # noqa
+
+    string_types = (basestring,)  # noqa
+    binary_type = str
+    text_type = unicode  # noqa
+
+    def u(s):
+        return unicode(s, "utf-8")  # noqa
+
+    def b(s):
+        return s
+
+    def octal(lit):
+        return eval("0" + lit)
+
+
+if py3k:
+    from importlib import machinery
+
+    def load_module(module_id, path):
+        return machinery.SourceFileLoader(module_id, path).load_module()
+
+
+else:
+    import imp
+
+    def load_module(module_id, path):
+        fp = open(path, "rb")
+        try:
+            return imp.load_source(module_id, path, fp)
+        finally:
+            fp.close()
+
+
+if py3k:
+
+    def reraise(tp, value, tb=None, cause=None):
+        if cause is not None:
+            value.__cause__ = cause
+        if value.__traceback__ is not tb:
+            raise value.with_traceback(tb)
+        raise value
+
+
+else:
+    exec(
+        "def reraise(tp, value, tb=None, cause=None):\n"
+        "    raise tp, value, tb\n"
+    )
+
+
+def exception_as():
+    return sys.exc_info()[1]
+
+
+all = all  # noqa
+
+
+def exception_name(exc):
+    return exc.__class__.__name__
+
+
+################################################
+# cross-compatible metaclass implementation
+# Copyright (c) 2010-2012 Benjamin Peterson
+def with_metaclass(meta, base=object):
+    """Create a base class with a metaclass."""
+    return meta("%sBase" % meta.__name__, (base,), {})
+
+
+################################################
+
+
+def arg_stringname(func_arg):
+    """Gets the string name of a kwarg or vararg
+    In Python3.4 a function's args are
+    of _ast.arg type not _ast.name
+    """
+    if hasattr(func_arg, "arg"):
+        return func_arg.arg
+    else:
+        return str(func_arg)
diff --git a/third_party/python/Mako/mako/exceptions.py b/third_party/python/Mako/mako/exceptions.py
new file mode 100644
index 0000000000..ea7b20dbdd
--- /dev/null
+++ b/third_party/python/Mako/mako/exceptions.py
@@ -0,0 +1,430 @@
+# mako/exceptions.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""exception classes"""
+
+import sys
+import traceback
+
+from mako import compat
+from mako import util
+
+
+class MakoException(Exception):
+    pass
+
+
+class RuntimeException(MakoException):
+    pass
+
+
+def _format_filepos(lineno, pos, filename):
+    if filename is None:
+        return " at line: %d char: %d" % (lineno, pos)
+    else:
+        return " in file '%s' at line: %d char: %d" % (filename, lineno, pos)
+
+
+class CompileException(MakoException):
+    def __init__(self, message, source, lineno, pos, filename):
+        MakoException.__init__(
+            self, message + _format_filepos(lineno, pos, filename)
+        )
+        self.lineno = lineno
+        self.pos = pos
+        self.filename = filename
+        self.source = source
+
+
+class SyntaxException(MakoException):
+    def __init__(self, message, source, lineno, pos, filename):
+        MakoException.__init__(
+            self, message + _format_filepos(lineno, pos, filename)
+        )
+        self.lineno = lineno
+        self.pos = pos
+        self.filename = filename
+        self.source = source
+
+
+class UnsupportedError(MakoException):
+
+    """raised when a retired feature is used."""
+
+
+class NameConflictError(MakoException):
+
+    """raised when a reserved word is used inappropriately"""
+
+
+class TemplateLookupException(MakoException):
+    pass
+
+
+class TopLevelLookupException(TemplateLookupException):
+    pass
+
+
+class RichTraceback(object):
+
+    """Pull the current exception from the ``sys`` traceback and extracts
+    Mako-specific template information.
+
+    See the usage examples in :ref:`handling_exceptions`.
+
+    """
+
+    def __init__(self, error=None, traceback=None):
+        self.source, self.lineno = "", 0
+
+        if error is None or traceback is None:
+            t, value, tback = sys.exc_info()
+
+        if error is None:
+            error = value or t
+
+        if traceback is None:
+            traceback = tback
+
+        self.error = error
+        self.records = self._init(traceback)
+
+        if isinstance(self.error, (CompileException, SyntaxException)):
+            self.source = self.error.source
+            self.lineno = self.error.lineno
+            self._has_source = True
+
+        self._init_message()
+
+    @property
+    def errorname(self):
+        return compat.exception_name(self.error)
+
+    def _init_message(self):
+        """Find a unicode representation of self.error"""
+        try:
+            self.message = compat.text_type(self.error)
+        except UnicodeError:
+            try:
+                self.message = str(self.error)
+            except UnicodeEncodeError:
+                # Fallback to args as neither unicode nor
+                # str(Exception(u'\xe6')) work in Python < 2.6
+                self.message = self.error.args[0]
+        if not isinstance(self.message, compat.text_type):
+            self.message = compat.text_type(self.message, "ascii", "replace")
+
+    def _get_reformatted_records(self, records):
+        for rec in records:
+            if rec[6] is not None:
+                yield (rec[4], rec[5], rec[2], rec[6])
+            else:
+                yield tuple(rec[0:4])
+
+    @property
+    def traceback(self):
+        """Return a list of 4-tuple traceback records (i.e. normal python
+        format) with template-corresponding lines remapped to the originating
+        template.
+
+        """
+        return list(self._get_reformatted_records(self.records))
+
+    @property
+    def reverse_records(self):
+        return reversed(self.records)
+
+    @property
+    def reverse_traceback(self):
+        """Return the same data as traceback, except in reverse order.
+        """
+
+        return list(self._get_reformatted_records(self.reverse_records))
+
+    def _init(self, trcback):
+        """format a traceback from sys.exc_info() into 7-item tuples,
+        containing the regular four traceback tuple items, plus the original
+        template filename, the line number adjusted relative to the template
+        source, and code line from that line number of the template."""
+
+        import mako.template
+
+        mods = {}
+        rawrecords = traceback.extract_tb(trcback)
+        new_trcback = []
+        for filename, lineno, function, line in rawrecords:
+            if not line:
+                line = ""
+            try:
+                (line_map, template_lines, template_filename) = mods[filename]
+            except KeyError:
+                try:
+                    info = mako.template._get_module_info(filename)
+                    module_source = info.code
+                    template_source = info.source
+                    template_filename = (
+                        info.template_filename or info.template_uri or filename
+                    )
+                except KeyError:
+                    # A normal .py file (not a Template)
+                    if not compat.py3k:
+                        try:
+                            fp = open(filename, "rb")
+                            encoding = util.parse_encoding(fp)
+                            fp.close()
+                        except IOError:
+                            encoding = None
+                        if encoding:
+                            line = line.decode(encoding)
+                        else:
+                            line = line.decode("ascii", "replace")
+                    new_trcback.append(
+                        (
+                            filename,
+                            lineno,
+                            function,
+                            line,
+                            None,
+                            None,
+                            None,
+                            None,
+                        )
+                    )
+                    continue
+
+                template_ln = 1
+
+                mtm = mako.template.ModuleInfo
+                source_map = mtm.get_module_source_metadata(
+                    module_source, full_line_map=True
+                )
+                line_map = source_map["full_line_map"]
+
+                template_lines = [
+                    line_ for line_ in template_source.split("\n")
+                ]
+                mods[filename] = (line_map, template_lines, template_filename)
+
+            template_ln = line_map[lineno - 1]
+
+            if template_ln <= len(template_lines):
+                template_line = template_lines[template_ln - 1]
+            else:
+                template_line = None
+            new_trcback.append(
+                (
+                    filename,
+                    lineno,
+                    function,
+                    line,
+                    template_filename,
+                    template_ln,
+                    template_line,
+                    template_source,
+                )
+            )
+        if not self.source:
+            for l in range(len(new_trcback) - 1, 0, -1):
+                if new_trcback[l][5]:
+                    self.source = new_trcback[l][7]
+                    self.lineno = new_trcback[l][5]
+                    break
+            else:
+                if new_trcback:
+                    try:
+                        # A normal .py file (not a Template)
+                        fp = open(new_trcback[-1][0], "rb")
+                        encoding = util.parse_encoding(fp)
+                        if compat.py3k and not encoding:
+                            encoding = "utf-8"
+                        fp.seek(0)
+                        self.source = fp.read()
+                        fp.close()
+                        if encoding:
+                            self.source = self.source.decode(encoding)
+                    except IOError:
+                        self.source = ""
+                    self.lineno = new_trcback[-1][1]
+        return new_trcback
+
+
+def text_error_template(lookup=None):
+    """Provides a template that renders a stack trace in a similar format to
+    the Python interpreter, substituting source template filenames, line
+    numbers and code for that of the originating source template, as
+    applicable.
+
+    """
+    import mako.template
+
+    return mako.template.Template(
+        r"""
+<%page args="error=None, traceback=None"/>
+<%!
+    from mako.exceptions import RichTraceback
+%>\
+<%
+    tback = RichTraceback(error=error, traceback=traceback)
+%>\
+Traceback (most recent call last):
+% for (filename, lineno, function, line) in tback.traceback:
+  File "${filename}", line ${lineno}, in ${function or '?'}
+    ${line | trim}
+% endfor
+${tback.errorname}: ${tback.message}
+"""
+    )
+
+
+def _install_pygments():
+    global syntax_highlight, pygments_html_formatter
+    from mako.ext.pygmentplugin import syntax_highlight  # noqa
+    from mako.ext.pygmentplugin import pygments_html_formatter  # noqa
+
+
+def _install_fallback():
+    global syntax_highlight, pygments_html_formatter
+    from mako.filters import html_escape
+
+    pygments_html_formatter = None
+
+    def syntax_highlight(filename="", language=None):
+        return html_escape
+
+
+def _install_highlighting():
+    try:
+        _install_pygments()
+    except ImportError:
+        _install_fallback()
+
+
+_install_highlighting()
+
+
+def html_error_template():
+    """Provides a template that renders a stack trace in an HTML format,
+    providing an excerpt of code as well as substituting source template
+    filenames, line numbers and code for that of the originating source
+    template, as applicable.
+
+    The template's default ``encoding_errors`` value is
+    ``'htmlentityreplace'``. The template has two options. With the
+    ``full`` option disabled, only a section of an HTML document is
+    returned. With the ``css`` option disabled, the default stylesheet
+    won't be included.
+
+    """
+    import mako.template
+
+    return mako.template.Template(
+        r"""
+<%!
+    from mako.exceptions import RichTraceback, syntax_highlight,\
+            pygments_html_formatter
+%>
+<%page args="full=True, css=True, error=None, traceback=None"/>
+% if full:
+<html>
+<head>
+    <title>Mako Runtime Error</title>
+% endif
+% if css:
+    <style>
+        body { font-family:verdana; margin:10px 30px 10px 30px;}
+        .stacktrace { margin:5px 5px 5px 5px; }
+        .highlight { padding:0px 10px 0px 10px; background-color:#9F9FDF; }
+        .nonhighlight { padding:0px; background-color:#DFDFDF; }
+        .sample { padding:10px; margin:10px 10px 10px 10px;
+                  font-family:monospace; }
+        .sampleline { padding:0px 10px 0px 10px; }
+        .sourceline { margin:5px 5px 10px 5px; font-family:monospace;}
+        .location { font-size:80%; }
+        .highlight { white-space:pre; }
+        .sampleline { white-space:pre; }
+
+    % if pygments_html_formatter:
+        ${pygments_html_formatter.get_style_defs()}
+        .linenos { min-width: 2.5em; text-align: right; }
+        pre { margin: 0; }
+        .syntax-highlighted { padding: 0 10px; }
+        .syntax-highlightedtable { border-spacing: 1px; }
+        .nonhighlight { border-top: 1px solid #DFDFDF;
+                        border-bottom: 1px solid #DFDFDF; }
+        .stacktrace .nonhighlight { margin: 5px 15px 10px; }
+        .sourceline { margin: 0 0; font-family:monospace; }
+        .code { background-color: #F8F8F8; width: 100%; }
+        .error .code { background-color: #FFBDBD; }
+        .error .syntax-highlighted { background-color: #FFBDBD; }
+    % endif
+
+    </style>
+% endif
+% if full:
+</head>
+<body>
+% endif
+
+<h2>Error !</h2>
+<%
+    tback = RichTraceback(error=error, traceback=traceback)
+    src = tback.source
+    line = tback.lineno
+    if src:
+        lines = src.split('\n')
+    else:
+        lines = None
+%>
+<h3>${tback.errorname}: ${tback.message|h}</h3>
+
+% if lines:
+    <div class="sample">
+    <div class="nonhighlight">
+% for index in range(max(0, line-4),min(len(lines), line+5)):
+    <%
+       if pygments_html_formatter:
+           pygments_html_formatter.linenostart = index + 1
+    %>
+    % if index + 1 == line:
+    <%
+       if pygments_html_formatter:
+           old_cssclass = pygments_html_formatter.cssclass
+           pygments_html_formatter.cssclass = 'error ' + old_cssclass
+    %>
+        ${lines[index] | syntax_highlight(language='mako')}
+    <%
+       if pygments_html_formatter:
+           pygments_html_formatter.cssclass = old_cssclass
+    %>
+    % else:
+        ${lines[index] | syntax_highlight(language='mako')}
+    % endif
+% endfor
+    </div>
+    </div>
+% endif
+
+<div class="stacktrace">
+% for (filename, lineno, function, line) in tback.reverse_traceback:
+    <div class="location">${filename}, line ${lineno}:</div>
+    <div class="nonhighlight">
+    <%
+       if pygments_html_formatter:
+           pygments_html_formatter.linenostart = lineno
+    %>
+      <div class="sourceline">${line | syntax_highlight(filename)}</div>
+    </div>
+% endfor
+</div>
+
+% if full:
+</body>
+</html>
+% endif
+""",
+        output_encoding=sys.getdefaultencoding(),
+        encoding_errors="htmlentityreplace",
+    )
diff --git a/third_party/python/Mako/mako/ext/__init__.py b/third_party/python/Mako/mako/ext/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/__init__.py
diff --git a/third_party/python/Mako/mako/ext/autohandler.py b/third_party/python/Mako/mako/ext/autohandler.py
new file mode 100644
index 0000000000..8b1324ef00
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/autohandler.py
@@ -0,0 +1,70 @@
+# ext/autohandler.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""adds autohandler functionality to Mako templates.
+
+requires that the TemplateLookup class is used with templates.
+
+usage::
+
+    <%!
+        from mako.ext.autohandler import autohandler
+    %>
+    <%inherit file="${autohandler(template, context)}"/>
+
+
+or with custom autohandler filename::
+
+    <%!
+        from mako.ext.autohandler import autohandler
+    %>
+    <%inherit file="${autohandler(template, context, name='somefilename')}"/>
+
+"""
+
+import os
+import posixpath
+import re
+
+
+def autohandler(template, context, name="autohandler"):
+    lookup = context.lookup
+    _template_uri = template.module._template_uri
+    if not lookup.filesystem_checks:
+        try:
+            return lookup._uri_cache[(autohandler, _template_uri, name)]
+        except KeyError:
+            pass
+
+    tokens = re.findall(r"([^/]+)", posixpath.dirname(_template_uri)) + [name]
+    while len(tokens):
+        path = "/" + "/".join(tokens)
+        if path != _template_uri and _file_exists(lookup, path):
+            if not lookup.filesystem_checks:
+                return lookup._uri_cache.setdefault(
+                    (autohandler, _template_uri, name), path
+                )
+            else:
+                return path
+        if len(tokens) == 1:
+            break
+        tokens[-2:] = [name]
+
+    if not lookup.filesystem_checks:
+        return lookup._uri_cache.setdefault(
+            (autohandler, _template_uri, name), None
+        )
+    else:
+        return None
+
+
+def _file_exists(lookup, path):
+    psub = re.sub(r"^/", "", path)
+    for d in lookup.directories:
+        if os.path.exists(d + "/" + psub):
+            return True
+    else:
+        return False
diff --git a/third_party/python/Mako/mako/ext/babelplugin.py b/third_party/python/Mako/mako/ext/babelplugin.py
new file mode 100644
index 0000000000..76bbc5b03f
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/babelplugin.py
@@ -0,0 +1,58 @@
+# ext/babelplugin.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""gettext message extraction via Babel: http://babel.edgewall.org/"""
+from babel.messages.extract import extract_python
+
+from mako.ext.extract import MessageExtractor
+
+
+class BabelMakoExtractor(MessageExtractor):
+    def __init__(self, keywords, comment_tags, options):
+        self.keywords = keywords
+        self.options = options
+        self.config = {
+            "comment-tags": u" ".join(comment_tags),
+            "encoding": options.get(
+                "input_encoding", options.get("encoding", None)
+            ),
+        }
+        super(BabelMakoExtractor, self).__init__()
+
+    def __call__(self, fileobj):
+        return self.process_file(fileobj)
+
+    def process_python(self, code, code_lineno, translator_strings):
+        comment_tags = self.config["comment-tags"]
+        for (
+            lineno,
+            funcname,
+            messages,
+            python_translator_comments,
+        ) in extract_python(code, self.keywords, comment_tags, self.options):
+            yield (
+                code_lineno + (lineno - 1),
+                funcname,
+                messages,
+                translator_strings + python_translator_comments,
+            )
+
+
+def extract(fileobj, keywords, comment_tags, options):
+    """Extract messages from Mako templates.
+
+    :param fileobj: the file-like object the messages should be extracted from
+    :param keywords: a list of keywords (i.e. function names) that should be
+                     recognized as translation functions
+    :param comment_tags: a list of translator tags to search for and include
+                         in the results
+    :param options: a dictionary of additional options (optional)
+    :return: an iterator over ``(lineno, funcname, message, comments)`` tuples
+    :rtype: ``iterator``
+    """
+    extractor = BabelMakoExtractor(keywords, comment_tags, options)
+    for message in extractor(fileobj):
+        yield message
diff --git a/third_party/python/Mako/mako/ext/beaker_cache.py b/third_party/python/Mako/mako/ext/beaker_cache.py
new file mode 100644
index 0000000000..f65ce43ae8
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/beaker_cache.py
@@ -0,0 +1,82 @@
+# ext/beaker_cache.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""Provide a :class:`.CacheImpl` for the Beaker caching system."""
+
+from mako import exceptions
+from mako.cache import CacheImpl
+
+try:
+    from beaker import cache as beaker_cache
+except:
+    has_beaker = False
+else:
+    has_beaker = True
+
+_beaker_cache = None
+
+
+class BeakerCacheImpl(CacheImpl):
+
+    """A :class:`.CacheImpl` provided for the Beaker caching system.
+
+    This plugin is used by default, based on the default
+    value of ``'beaker'`` for the ``cache_impl`` parameter of the
+    :class:`.Template` or :class:`.TemplateLookup` classes.
+
+    """
+
+    def __init__(self, cache):
+        if not has_beaker:
+            raise exceptions.RuntimeException(
+                "Can't initialize Beaker plugin; Beaker is not installed."
+            )
+        global _beaker_cache
+        if _beaker_cache is None:
+            if "manager" in cache.template.cache_args:
+                _beaker_cache = cache.template.cache_args["manager"]
+            else:
+                _beaker_cache = beaker_cache.CacheManager()
+        super(BeakerCacheImpl, self).__init__(cache)
+
+    def _get_cache(self, **kw):
+        expiretime = kw.pop("timeout", None)
+        if "dir" in kw:
+            kw["data_dir"] = kw.pop("dir")
+        elif self.cache.template.module_directory:
+            kw["data_dir"] = self.cache.template.module_directory
+
+        if "manager" in kw:
+            kw.pop("manager")
+
+        if kw.get("type") == "memcached":
+            kw["type"] = "ext:memcached"
+
+        if "region" in kw:
+            region = kw.pop("region")
+            cache = _beaker_cache.get_cache_region(self.cache.id, region, **kw)
+        else:
+            cache = _beaker_cache.get_cache(self.cache.id, **kw)
+        cache_args = {"starttime": self.cache.starttime}
+        if expiretime:
+            cache_args["expiretime"] = expiretime
+        return cache, cache_args
+
+    def get_or_create(self, key, creation_function, **kw):
+        cache, kw = self._get_cache(**kw)
+        return cache.get(key, createfunc=creation_function, **kw)
+
+    def put(self, key, value, **kw):
+        cache, kw = self._get_cache(**kw)
+        cache.put(key, value, **kw)
+
+    def get(self, key, **kw):
+        cache, kw = self._get_cache(**kw)
+        return cache.get(key, **kw)
+
+    def invalidate(self, key, **kw):
+        cache, kw = self._get_cache(**kw)
+        cache.remove_value(key, **kw)
diff --git a/third_party/python/Mako/mako/ext/extract.py b/third_party/python/Mako/mako/ext/extract.py
new file mode 100644
index 0000000000..ad2348a523
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/extract.py
@@ -0,0 +1,125 @@
+# ext/extract.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+import re
+
+from mako import compat
+from mako import lexer
+from mako import parsetree
+
+
+class MessageExtractor(object):
+    def process_file(self, fileobj):
+        template_node = lexer.Lexer(
+            fileobj.read(), input_encoding=self.config["encoding"]
+        ).parse()
+        for extracted in self.extract_nodes(template_node.get_children()):
+            yield extracted
+
+    def extract_nodes(self, nodes):
+        translator_comments = []
+        in_translator_comments = False
+        input_encoding = self.config["encoding"] or "ascii"
+        comment_tags = list(
+            filter(None, re.split(r"\s+", self.config["comment-tags"]))
+        )
+
+        for node in nodes:
+            child_nodes = None
+            if (
+                in_translator_comments
+                and isinstance(node, parsetree.Text)
+                and not node.content.strip()
+            ):
+                # Ignore whitespace within translator comments
+                continue
+
+            if isinstance(node, parsetree.Comment):
+                value = node.text.strip()
+                if in_translator_comments:
+                    translator_comments.extend(
+                        self._split_comment(node.lineno, value)
+                    )
+                    continue
+                for comment_tag in comment_tags:
+                    if value.startswith(comment_tag):
+                        in_translator_comments = True
+                        translator_comments.extend(
+                            self._split_comment(node.lineno, value)
+                        )
+                continue
+
+            if isinstance(node, parsetree.DefTag):
+                code = node.function_decl.code
+                child_nodes = node.nodes
+            elif isinstance(node, parsetree.BlockTag):
+                code = node.body_decl.code
+                child_nodes = node.nodes
+            elif isinstance(node, parsetree.CallTag):
+                code = node.code.code
+                child_nodes = node.nodes
+            elif isinstance(node, parsetree.PageTag):
+                code = node.body_decl.code
+            elif isinstance(node, parsetree.CallNamespaceTag):
+                code = node.expression
+                child_nodes = node.nodes
+            elif isinstance(node, parsetree.ControlLine):
+                if node.isend:
+                    in_translator_comments = False
+                    continue
+                code = node.text
+            elif isinstance(node, parsetree.Code):
+                in_translator_comments = False
+                code = node.code.code
+            elif isinstance(node, parsetree.Expression):
+                code = node.code.code
+            else:
+                continue
+
+            # Comments don't apply unless they immediately precede the message
+            if (
+                translator_comments
+                and translator_comments[-1][0] < node.lineno - 1
+            ):
+                translator_comments = []
+
+            translator_strings = [
+                comment[1] for comment in translator_comments
+            ]
+
+            if isinstance(code, compat.text_type):
+                code = code.encode(input_encoding, "backslashreplace")
+
+            used_translator_comments = False
+            # We add extra newline to work around a pybabel bug
+            # (see python-babel/babel#274, parse_encoding dies if the first
+            # input string of the input is non-ascii)
+            # Also, because we added it, we have to subtract one from
+            # node.lineno
+            code = compat.byte_buffer(compat.b("\n") + code)
+
+            for message in self.process_python(
+                code, node.lineno - 1, translator_strings
+            ):
+                yield message
+                used_translator_comments = True
+
+            if used_translator_comments:
+                translator_comments = []
+            in_translator_comments = False
+
+            if child_nodes:
+                for extracted in self.extract_nodes(child_nodes):
+                    yield extracted
+
+    @staticmethod
+    def _split_comment(lineno, comment):
+        """Return the multiline comment at lineno split into a list of
+        comment line numbers and the accompanying comment line"""
+        return [
+            (lineno + index, line)
+            for index, line in enumerate(comment.splitlines())
+        ]
diff --git a/third_party/python/Mako/mako/ext/linguaplugin.py b/third_party/python/Mako/mako/ext/linguaplugin.py
new file mode 100644
index 0000000000..0f6d165a2f
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/linguaplugin.py
@@ -0,0 +1,57 @@
+# ext/linguaplugin.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+import io
+
+from lingua.extractors import Extractor
+from lingua.extractors import get_extractor
+from lingua.extractors import Message
+
+from mako import compat
+from mako.ext.extract import MessageExtractor
+
+
+class LinguaMakoExtractor(Extractor, MessageExtractor):
+
+    """Mako templates"""
+
+    extensions = [".mako"]
+    default_config = {"encoding": "utf-8", "comment-tags": ""}
+
+    def __call__(self, filename, options, fileobj=None):
+        self.options = options
+        self.filename = filename
+        self.python_extractor = get_extractor("x.py")
+        if fileobj is None:
+            fileobj = open(filename, "rb")
+        return self.process_file(fileobj)
+
+    def process_python(self, code, code_lineno, translator_strings):
+        source = code.getvalue().strip()
+        if source.endswith(compat.b(":")):
+            if source in (
+                compat.b("try:"),
+                compat.b("else:"),
+            ) or source.startswith(compat.b("except")):
+                source = compat.b("")  # Ignore try/except and else
+            elif source.startswith(compat.b("elif")):
+                source = source[2:]  # Replace "elif" with "if"
+            source += compat.b("pass")
+        code = io.BytesIO(source)
+        for msg in self.python_extractor(
+            self.filename, self.options, code, code_lineno - 1
+        ):
+            if translator_strings:
+                msg = Message(
+                    msg.msgctxt,
+                    msg.msgid,
+                    msg.msgid_plural,
+                    msg.flags,
+                    compat.u(" ").join(translator_strings + [msg.comment]),
+                    msg.tcomment,
+                    msg.location,
+                )
+            yield msg
diff --git a/third_party/python/Mako/mako/ext/preprocessors.py b/third_party/python/Mako/mako/ext/preprocessors.py
new file mode 100644
index 0000000000..9cc0621482
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/preprocessors.py
@@ -0,0 +1,20 @@
+# ext/preprocessors.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""preprocessing functions, used with the 'preprocessor'
+argument on Template, TemplateLookup"""
+
+import re
+
+
+def convert_comments(text):
+    """preprocess old style comments.
+
+    example:
+
+    from mako.ext.preprocessors import convert_comments
+    t = Template(..., preprocessor=convert_comments)"""
+    return re.sub(r"(?<=\n)\s*#[^#]", "##", text)
diff --git a/third_party/python/Mako/mako/ext/pygmentplugin.py b/third_party/python/Mako/mako/ext/pygmentplugin.py
new file mode 100644
index 0000000000..943a67a49c
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/pygmentplugin.py
@@ -0,0 +1,157 @@
+# ext/pygmentplugin.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+from pygments import highlight
+from pygments.formatters.html import HtmlFormatter
+from pygments.lexer import bygroups
+from pygments.lexer import DelegatingLexer
+from pygments.lexer import include
+from pygments.lexer import RegexLexer
+from pygments.lexer import using
+from pygments.lexers.agile import Python3Lexer
+from pygments.lexers.agile import PythonLexer
+from pygments.lexers.web import CssLexer
+from pygments.lexers.web import HtmlLexer
+from pygments.lexers.web import JavascriptLexer
+from pygments.lexers.web import XmlLexer
+from pygments.token import Comment
+from pygments.token import Keyword
+from pygments.token import Name
+from pygments.token import Operator
+from pygments.token import Other
+from pygments.token import String
+from pygments.token import Text
+
+from mako import compat
+
+
+class MakoLexer(RegexLexer):
+    name = "Mako"
+    aliases = ["mako"]
+    filenames = ["*.mao"]
+
+    tokens = {
+        "root": [
+            (
+                r"(\s*)(\%)(\s*end(?:\w+))(\n|\Z)",
+                bygroups(Text, Comment.Preproc, Keyword, Other),
+            ),
+            (
+                r"(\s*)(\%(?!%))([^\n]*)(\n|\Z)",
+                bygroups(Text, Comment.Preproc, using(PythonLexer), Other),
+            ),
+            (
+                r"(\s*)(##[^\n]*)(\n|\Z)",
+                bygroups(Text, Comment.Preproc, Other),
+            ),
+            (r"""(?s)<%doc>.*?</%doc>""", Comment.Preproc),
+            (
+                r"(<%)([\w\.\:]+)",
+                bygroups(Comment.Preproc, Name.Builtin),
+                "tag",
+            ),
+            (
+                r"(</%)([\w\.\:]+)(>)",
+                bygroups(Comment.Preproc, Name.Builtin, Comment.Preproc),
+            ),
+            (r"<%(?=([\w\.\:]+))", Comment.Preproc, "ondeftags"),
+            (
+                r"(?s)(<%(?:!?))(.*?)(%>)",
+                bygroups(Comment.Preproc, using(PythonLexer), Comment.Preproc),
+            ),
+            (
+                r"(\$\{)(.*?)(\})",
+                bygroups(Comment.Preproc, using(PythonLexer), Comment.Preproc),
+            ),
+            (
+                r"""(?sx)
+                (.+?)               # anything, followed by:
+                (?:
+                 (?<=\n)(?=%(?!%)|\#\#) |  # an eval or comment line
+                 (?=\#\*) |          # multiline comment
+                 (?=</?%) |         # a python block
+                                    # call start or end
+                 (?=\$\{) |         # a substitution
+                 (?<=\n)(?=\s*%) |
+                                    # - don't consume
+                 (\\\n) |           # an escaped newline
+                 \Z                 # end of string
+                )
+            """,
+                bygroups(Other, Operator),
+            ),
+            (r"\s+", Text),
+        ],
+        "ondeftags": [
+            (r"<%", Comment.Preproc),
+            (r"(?<=<%)(include|inherit|namespace|page)", Name.Builtin),
+            include("tag"),
+        ],
+        "tag": [
+            (r'((?:\w+)\s*=)\s*(".*?")', bygroups(Name.Attribute, String)),
+            (r"/?\s*>", Comment.Preproc, "#pop"),
+            (r"\s+", Text),
+        ],
+        "attr": [
+            ('".*?"', String, "#pop"),
+            ("'.*?'", String, "#pop"),
+            (r"[^\s>]+", String, "#pop"),
+        ],
+    }
+
+
+class MakoHtmlLexer(DelegatingLexer):
+    name = "HTML+Mako"
+    aliases = ["html+mako"]
+
+    def __init__(self, **options):
+        super(MakoHtmlLexer, self).__init__(HtmlLexer, MakoLexer, **options)
+
+
+class MakoXmlLexer(DelegatingLexer):
+    name = "XML+Mako"
+    aliases = ["xml+mako"]
+
+    def __init__(self, **options):
+        super(MakoXmlLexer, self).__init__(XmlLexer, MakoLexer, **options)
+
+
+class MakoJavascriptLexer(DelegatingLexer):
+    name = "JavaScript+Mako"
+    aliases = ["js+mako", "javascript+mako"]
+
+    def __init__(self, **options):
+        super(MakoJavascriptLexer, self).__init__(
+            JavascriptLexer, MakoLexer, **options
+        )
+
+
+class MakoCssLexer(DelegatingLexer):
+    name = "CSS+Mako"
+    aliases = ["css+mako"]
+
+    def __init__(self, **options):
+        super(MakoCssLexer, self).__init__(CssLexer, MakoLexer, **options)
+
+
+pygments_html_formatter = HtmlFormatter(
+    cssclass="syntax-highlighted", linenos=True
+)
+
+
+def syntax_highlight(filename="", language=None):
+    mako_lexer = MakoLexer()
+    if compat.py3k:
+        python_lexer = Python3Lexer()
+    else:
+        python_lexer = PythonLexer()
+    if filename.startswith("memory:") or language == "mako":
+        return lambda string: highlight(
+            string, mako_lexer, pygments_html_formatter
+        )
+    return lambda string: highlight(
+        string, python_lexer, pygments_html_formatter
+    )
diff --git a/third_party/python/Mako/mako/ext/turbogears.py b/third_party/python/Mako/mako/ext/turbogears.py
new file mode 100644
index 0000000000..722a6b4b40
--- /dev/null
+++ b/third_party/python/Mako/mako/ext/turbogears.py
@@ -0,0 +1,61 @@
+# ext/turbogears.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+from mako import compat
+from mako.lookup import TemplateLookup
+from mako.template import Template
+
+
+class TGPlugin(object):
+
+    """TurboGears compatible Template Plugin."""
+
+    def __init__(self, extra_vars_func=None, options=None, extension="mak"):
+        self.extra_vars_func = extra_vars_func
+        self.extension = extension
+        if not options:
+            options = {}
+
+        # Pull the options out and initialize the lookup
+        lookup_options = {}
+        for k, v in options.items():
+            if k.startswith("mako."):
+                lookup_options[k[5:]] = v
+            elif k in ["directories", "filesystem_checks", "module_directory"]:
+                lookup_options[k] = v
+        self.lookup = TemplateLookup(**lookup_options)
+
+        self.tmpl_options = {}
+        # transfer lookup args to template args, based on those available
+        # in getargspec
+        for kw in compat.inspect_getargspec(Template.__init__)[0]:
+            if kw in lookup_options:
+                self.tmpl_options[kw] = lookup_options[kw]
+
+    def load_template(self, templatename, template_string=None):
+        """Loads a template from a file or a string"""
+        if template_string is not None:
+            return Template(template_string, **self.tmpl_options)
+        # Translate TG dot notation to normal / template path
+        if "/" not in templatename:
+            templatename = (
+                "/" + templatename.replace(".", "/") + "." + self.extension
+            )
+
+        # Lookup template
+        return self.lookup.get_template(templatename)
+
+    def render(
+        self, info, format="html", fragment=False, template=None  # noqa
+    ):
+        if isinstance(template, compat.string_types):
+            template = self.load_template(template)
+
+        # Load extra vars func if provided
+        if self.extra_vars_func:
+            info.update(self.extra_vars_func())
+
+        return template.render(**info)
diff --git a/third_party/python/Mako/mako/filters.py b/third_party/python/Mako/mako/filters.py
new file mode 100644
index 0000000000..0ae33ff486
--- /dev/null
+++ b/third_party/python/Mako/mako/filters.py
@@ -0,0 +1,219 @@
+# mako/filters.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+
+import codecs
+import re
+
+from mako import compat
+from mako.compat import codepoint2name
+from mako.compat import name2codepoint
+from mako.compat import quote_plus
+from mako.compat import unquote_plus
+
+xml_escapes = {
+    "&": "&amp;",
+    ">": "&gt;",
+    "<": "&lt;",
+    '"': "&#34;",  # also &quot; in html-only
+    "'": "&#39;",  # also &apos; in html-only
+}
+
+# XXX: &quot; is valid in HTML and XML
+#      &apos; is not valid HTML, but is valid XML
+
+
+def legacy_html_escape(s):
+    """legacy HTML escape for non-unicode mode."""
+    s = s.replace("&", "&amp;")
+    s = s.replace(">", "&gt;")
+    s = s.replace("<", "&lt;")
+    s = s.replace('"', "&#34;")
+    s = s.replace("'", "&#39;")
+    return s
+
+
+try:
+    import markupsafe
+
+    html_escape = markupsafe.escape
+except ImportError:
+    html_escape = legacy_html_escape
+
+
+def xml_escape(string):
+    return re.sub(r'([&<"\'>])', lambda m: xml_escapes[m.group()], string)
+
+
+def url_escape(string):
+    # convert into a list of octets
+    string = string.encode("utf8")
+    return quote_plus(string)
+
+
+def legacy_url_escape(string):
+    # convert into a list of octets
+    return quote_plus(string)
+
+
+def url_unescape(string):
+    text = unquote_plus(string)
+    if not is_ascii_str(text):
+        text = text.decode("utf8")
+    return text
+
+
+def trim(string):
+    return string.strip()
+
+
+class Decode(object):
+    def __getattr__(self, key):
+        def decode(x):
+            if isinstance(x, compat.text_type):
+                return x
+            elif not isinstance(x, compat.binary_type):
+                return decode(str(x))
+            else:
+                return compat.text_type(x, encoding=key)
+
+        return decode
+
+
+decode = Decode()
+
+
+_ASCII_re = re.compile(r"\A[\x00-\x7f]*\Z")
+
+
+def is_ascii_str(text):
+    return isinstance(text, str) and _ASCII_re.match(text)
+
+
+################################################################
+
+
+class XMLEntityEscaper(object):
+    def __init__(self, codepoint2name, name2codepoint):
+        self.codepoint2entity = dict(
+            [
+                (c, compat.text_type("&%s;" % n))
+                for c, n in codepoint2name.items()
+            ]
+        )
+        self.name2codepoint = name2codepoint
+
+    def escape_entities(self, text):
+        """Replace characters with their character entity references.
+
+        Only characters corresponding to a named entity are replaced.
+        """
+        return compat.text_type(text).translate(self.codepoint2entity)
+
+    def __escape(self, m):
+        codepoint = ord(m.group())
+        try:
+            return self.codepoint2entity[codepoint]
+        except (KeyError, IndexError):
+            return "&#x%X;" % codepoint
+
+    __escapable = re.compile(r'["&<>]|[^\x00-\x7f]')
+
+    def escape(self, text):
+        """Replace characters with their character references.
+
+        Replace characters by their named entity references.
+        Non-ASCII characters, if they do not have a named entity reference,
+        are replaced by numerical character references.
+
+        The return value is guaranteed to be ASCII.
+        """
+        return self.__escapable.sub(
+            self.__escape, compat.text_type(text)
+        ).encode("ascii")
+
+    # XXX: This regexp will not match all valid XML entity names__.
+    # (It punts on details involving involving CombiningChars and Extenders.)
+    #
+    # .. __: http://www.w3.org/TR/2000/REC-xml-20001006#NT-EntityRef
+    __characterrefs = re.compile(
+        r"""& (?:
+                                          \#(\d+)
+                                          | \#x([\da-f]+)
+                                          | ( (?!\d) [:\w] [-.:\w]+ )
+                                          ) ;""",
+        re.X | re.UNICODE,
+    )
+
+    def __unescape(self, m):
+        dval, hval, name = m.groups()
+        if dval:
+            codepoint = int(dval)
+        elif hval:
+            codepoint = int(hval, 16)
+        else:
+            codepoint = self.name2codepoint.get(name, 0xFFFD)
+            # U+FFFD = "REPLACEMENT CHARACTER"
+        if codepoint < 128:
+            return chr(codepoint)
+        return chr(codepoint)
+
+    def unescape(self, text):
+        """Unescape character references.
+
+        All character references (both entity references and numerical
+        character references) are unescaped.
+        """
+        return self.__characterrefs.sub(self.__unescape, text)
+
+
+_html_entities_escaper = XMLEntityEscaper(codepoint2name, name2codepoint)
+
+html_entities_escape = _html_entities_escaper.escape_entities
+html_entities_unescape = _html_entities_escaper.unescape
+
+
+def htmlentityreplace_errors(ex):
+    """An encoding error handler.
+
+    This python codecs error handler replaces unencodable
+    characters with HTML entities, or, if no HTML entity exists for
+    the character, XML character references::
+
+        >>> u'The cost was \u20ac12.'.encode('latin1', 'htmlentityreplace')
+        'The cost was &euro;12.'
+    """
+    if isinstance(ex, UnicodeEncodeError):
+        # Handle encoding errors
+        bad_text = ex.object[ex.start : ex.end]
+        text = _html_entities_escaper.escape(bad_text)
+        return (compat.text_type(text), ex.end)
+    raise ex
+
+
+codecs.register_error("htmlentityreplace", htmlentityreplace_errors)
+
+
+# TODO: options to make this dynamic per-compilation will be added in a later
+# release
+DEFAULT_ESCAPES = {
+    "x": "filters.xml_escape",
+    "h": "filters.html_escape",
+    "u": "filters.url_escape",
+    "trim": "filters.trim",
+    "entity": "filters.html_entities_escape",
+    "unicode": "unicode",
+    "decode": "decode",
+    "str": "str",
+    "n": "n",
+}
+
+if compat.py3k:
+    DEFAULT_ESCAPES.update({"unicode": "str"})
+
+NON_UNICODE_ESCAPES = DEFAULT_ESCAPES.copy()
+NON_UNICODE_ESCAPES["h"] = "filters.legacy_html_escape"
+NON_UNICODE_ESCAPES["u"] = "filters.legacy_url_escape"
diff --git a/third_party/python/Mako/mako/lexer.py b/third_party/python/Mako/mako/lexer.py
new file mode 100644
index 0000000000..a02b57f8a1
--- /dev/null
+++ b/third_party/python/Mako/mako/lexer.py
@@ -0,0 +1,490 @@
+# mako/lexer.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""provides the Lexer class for parsing template strings into parse trees."""
+
+import codecs
+import re
+
+from mako import compat
+from mako import exceptions
+from mako import parsetree
+from mako.pygen import adjust_whitespace
+
+_regexp_cache = {}
+
+
+class Lexer(object):
+    def __init__(
+        self,
+        text,
+        filename=None,
+        disable_unicode=False,
+        input_encoding=None,
+        preprocessor=None,
+    ):
+        self.text = text
+        self.filename = filename
+        self.template = parsetree.TemplateNode(self.filename)
+        self.matched_lineno = 1
+        self.matched_charpos = 0
+        self.lineno = 1
+        self.match_position = 0
+        self.tag = []
+        self.control_line = []
+        self.ternary_stack = []
+        self.disable_unicode = disable_unicode
+        self.encoding = input_encoding
+
+        if compat.py3k and disable_unicode:
+            raise exceptions.UnsupportedError(
+                "Mako for Python 3 does not " "support disabling Unicode"
+            )
+
+        if preprocessor is None:
+            self.preprocessor = []
+        elif not hasattr(preprocessor, "__iter__"):
+            self.preprocessor = [preprocessor]
+        else:
+            self.preprocessor = preprocessor
+
+    @property
+    def exception_kwargs(self):
+        return {
+            "source": self.text,
+            "lineno": self.matched_lineno,
+            "pos": self.matched_charpos,
+            "filename": self.filename,
+        }
+
+    def match(self, regexp, flags=None):
+        """compile the given regexp, cache the reg, and call match_reg()."""
+
+        try:
+            reg = _regexp_cache[(regexp, flags)]
+        except KeyError:
+            if flags:
+                reg = re.compile(regexp, flags)
+            else:
+                reg = re.compile(regexp)
+            _regexp_cache[(regexp, flags)] = reg
+
+        return self.match_reg(reg)
+
+    def match_reg(self, reg):
+        """match the given regular expression object to the current text
+        position.
+
+        if a match occurs, update the current text and line position.
+
+        """
+
+        mp = self.match_position
+
+        match = reg.match(self.text, self.match_position)
+        if match:
+            (start, end) = match.span()
+            if end == start:
+                self.match_position = end + 1
+            else:
+                self.match_position = end
+            self.matched_lineno = self.lineno
+            lines = re.findall(r"\n", self.text[mp : self.match_position])
+            cp = mp - 1
+            while cp >= 0 and cp < self.textlength and self.text[cp] != "\n":
+                cp -= 1
+            self.matched_charpos = mp - cp
+            self.lineno += len(lines)
+            # print "MATCHED:", match.group(0), "LINE START:",
+            # self.matched_lineno, "LINE END:", self.lineno
+        # print "MATCH:", regexp, "\n", self.text[mp : mp + 15], \
+        #          (match and "TRUE" or "FALSE")
+        return match
+
+    def parse_until_text(self, watch_nesting, *text):
+        startpos = self.match_position
+        text_re = r"|".join(text)
+        brace_level = 0
+        paren_level = 0
+        bracket_level = 0
+        while True:
+            match = self.match(r"#.*\n")
+            if match:
+                continue
+            match = self.match(
+                r"(\"\"\"|\'\'\'|\"|\')[^\\]*?(\\.[^\\]*?)*\1", re.S
+            )
+            if match:
+                continue
+            match = self.match(r"(%s)" % text_re)
+            if match and not (
+                watch_nesting
+                and (brace_level > 0 or paren_level > 0 or bracket_level > 0)
+            ):
+                return (
+                    self.text[
+                        startpos : self.match_position - len(match.group(1))
+                    ],
+                    match.group(1),
+                )
+            elif not match:
+                match = self.match(r"(.*?)(?=\"|\'|#|%s)" % text_re, re.S)
+            if match:
+                brace_level += match.group(1).count("{")
+                brace_level -= match.group(1).count("}")
+                paren_level += match.group(1).count("(")
+                paren_level -= match.group(1).count(")")
+                bracket_level += match.group(1).count("[")
+                bracket_level -= match.group(1).count("]")
+                continue
+            raise exceptions.SyntaxException(
+                "Expected: %s" % ",".join(text), **self.exception_kwargs
+            )
+
+    def append_node(self, nodecls, *args, **kwargs):
+        kwargs.setdefault("source", self.text)
+        kwargs.setdefault("lineno", self.matched_lineno)
+        kwargs.setdefault("pos", self.matched_charpos)
+        kwargs["filename"] = self.filename
+        node = nodecls(*args, **kwargs)
+        if len(self.tag):
+            self.tag[-1].nodes.append(node)
+        else:
+            self.template.nodes.append(node)
+        # build a set of child nodes for the control line
+        # (used for loop variable detection)
+        # also build a set of child nodes on ternary control lines
+        # (used for determining if a pass needs to be auto-inserted
+        if self.control_line:
+            control_frame = self.control_line[-1]
+            control_frame.nodes.append(node)
+            if not (
+                isinstance(node, parsetree.ControlLine)
+                and control_frame.is_ternary(node.keyword)
+            ):
+                if self.ternary_stack and self.ternary_stack[-1]:
+                    self.ternary_stack[-1][-1].nodes.append(node)
+        if isinstance(node, parsetree.Tag):
+            if len(self.tag):
+                node.parent = self.tag[-1]
+            self.tag.append(node)
+        elif isinstance(node, parsetree.ControlLine):
+            if node.isend:
+                self.control_line.pop()
+                self.ternary_stack.pop()
+            elif node.is_primary:
+                self.control_line.append(node)
+                self.ternary_stack.append([])
+            elif self.control_line and self.control_line[-1].is_ternary(
+                node.keyword
+            ):
+                self.ternary_stack[-1].append(node)
+            elif self.control_line and not self.control_line[-1].is_ternary(
+                node.keyword
+            ):
+                raise exceptions.SyntaxException(
+                    "Keyword '%s' not a legal ternary for keyword '%s'"
+                    % (node.keyword, self.control_line[-1].keyword),
+                    **self.exception_kwargs
+                )
+
+    _coding_re = re.compile(r"#.*coding[:=]\s*([-\w.]+).*\r?\n")
+
+    def decode_raw_stream(self, text, decode_raw, known_encoding, filename):
+        """given string/unicode or bytes/string, determine encoding
+           from magic encoding comment, return body as unicode
+           or raw if decode_raw=False
+
+        """
+        if isinstance(text, compat.text_type):
+            m = self._coding_re.match(text)
+            encoding = m and m.group(1) or known_encoding or "ascii"
+            return encoding, text
+
+        if text.startswith(codecs.BOM_UTF8):
+            text = text[len(codecs.BOM_UTF8) :]
+            parsed_encoding = "utf-8"
+            m = self._coding_re.match(text.decode("utf-8", "ignore"))
+            if m is not None and m.group(1) != "utf-8":
+                raise exceptions.CompileException(
+                    "Found utf-8 BOM in file, with conflicting "
+                    "magic encoding comment of '%s'" % m.group(1),
+                    text.decode("utf-8", "ignore"),
+                    0,
+                    0,
+                    filename,
+                )
+        else:
+            m = self._coding_re.match(text.decode("utf-8", "ignore"))
+            if m:
+                parsed_encoding = m.group(1)
+            else:
+                parsed_encoding = known_encoding or "ascii"
+
+        if decode_raw:
+            try:
+                text = text.decode(parsed_encoding)
+            except UnicodeDecodeError:
+                raise exceptions.CompileException(
+                    "Unicode decode operation of encoding '%s' failed"
+                    % parsed_encoding,
+                    text.decode("utf-8", "ignore"),
+                    0,
+                    0,
+                    filename,
+                )
+
+        return parsed_encoding, text
+
+    def parse(self):
+        self.encoding, self.text = self.decode_raw_stream(
+            self.text, not self.disable_unicode, self.encoding, self.filename
+        )
+
+        for preproc in self.preprocessor:
+            self.text = preproc(self.text)
+
+        # push the match marker past the
+        # encoding comment.
+        self.match_reg(self._coding_re)
+
+        self.textlength = len(self.text)
+
+        while True:
+            if self.match_position > self.textlength:
+                break
+
+            if self.match_end():
+                break
+            if self.match_expression():
+                continue
+            if self.match_control_line():
+                continue
+            if self.match_comment():
+                continue
+            if self.match_tag_start():
+                continue
+            if self.match_tag_end():
+                continue
+            if self.match_python_block():
+                continue
+            if self.match_text():
+                continue
+
+            if self.match_position > self.textlength:
+                break
+            raise exceptions.CompileException("assertion failed")
+
+        if len(self.tag):
+            raise exceptions.SyntaxException(
+                "Unclosed tag: <%%%s>" % self.tag[-1].keyword,
+                **self.exception_kwargs
+            )
+        if len(self.control_line):
+            raise exceptions.SyntaxException(
+                "Unterminated control keyword: '%s'"
+                % self.control_line[-1].keyword,
+                self.text,
+                self.control_line[-1].lineno,
+                self.control_line[-1].pos,
+                self.filename,
+            )
+        return self.template
+
+    def match_tag_start(self):
+        match = self.match(
+            r"""
+            \<%     # opening tag
+
+            ([\w\.\:]+)   # keyword
+
+            ((?:\s+\w+|\s*=\s*|".*?"|'.*?')*)  # attrname, = \
+                                               #        sign, string expression
+
+            \s*     # more whitespace
+
+            (/)?>   # closing
+
+            """,
+            re.I | re.S | re.X,
+        )
+
+        if match:
+            keyword, attr, isend = match.groups()
+            self.keyword = keyword
+            attributes = {}
+            if attr:
+                for att in re.findall(
+                    r"\s*(\w+)\s*=\s*(?:'([^']*)'|\"([^\"]*)\")", attr
+                ):
+                    key, val1, val2 = att
+                    text = val1 or val2
+                    text = text.replace("\r\n", "\n")
+                    attributes[key] = text
+            self.append_node(parsetree.Tag, keyword, attributes)
+            if isend:
+                self.tag.pop()
+            else:
+                if keyword == "text":
+                    match = self.match(r"(.*?)(?=\</%text>)", re.S)
+                    if not match:
+                        raise exceptions.SyntaxException(
+                            "Unclosed tag: <%%%s>" % self.tag[-1].keyword,
+                            **self.exception_kwargs
+                        )
+                    self.append_node(parsetree.Text, match.group(1))
+                    return self.match_tag_end()
+            return True
+        else:
+            return False
+
+    def match_tag_end(self):
+        match = self.match(r"\</%[\t ]*(.+?)[\t ]*>")
+        if match:
+            if not len(self.tag):
+                raise exceptions.SyntaxException(
+                    "Closing tag without opening tag: </%%%s>"
+                    % match.group(1),
+                    **self.exception_kwargs
+                )
+            elif self.tag[-1].keyword != match.group(1):
+                raise exceptions.SyntaxException(
+                    "Closing tag </%%%s> does not match tag: <%%%s>"
+                    % (match.group(1), self.tag[-1].keyword),
+                    **self.exception_kwargs
+                )
+            self.tag.pop()
+            return True
+        else:
+            return False
+
+    def match_end(self):
+        match = self.match(r"\Z", re.S)
+        if match:
+            string = match.group()
+            if string:
+                return string
+            else:
+                return True
+        else:
+            return False
+
+    def match_text(self):
+        match = self.match(
+            r"""
+                (.*?)         # anything, followed by:
+                (
+                 (?<=\n)(?=[ \t]*(?=%|\#\#)) # an eval or line-based
+                                             # comment preceded by a
+                                             # consumed newline and whitespace
+                 |
+                 (?=\${)      # an expression
+                 |
+                 (?=</?[%&])  # a substitution or block or call start or end
+                              # - don't consume
+                 |
+                 (\\\r?\n)    # an escaped newline  - throw away
+                 |
+                 \Z           # end of string
+                )""",
+            re.X | re.S,
+        )
+
+        if match:
+            text = match.group(1)
+            if text:
+                self.append_node(parsetree.Text, text)
+            return True
+        else:
+            return False
+
+    def match_python_block(self):
+        match = self.match(r"<%(!)?")
+        if match:
+            line, pos = self.matched_lineno, self.matched_charpos
+            text, end = self.parse_until_text(False, r"%>")
+            # the trailing newline helps
+            # compiler.parse() not complain about indentation
+            text = adjust_whitespace(text) + "\n"
+            self.append_node(
+                parsetree.Code,
+                text,
+                match.group(1) == "!",
+                lineno=line,
+                pos=pos,
+            )
+            return True
+        else:
+            return False
+
+    def match_expression(self):
+        match = self.match(r"\${")
+        if match:
+            line, pos = self.matched_lineno, self.matched_charpos
+            text, end = self.parse_until_text(True, r"\|", r"}")
+            if end == "|":
+                escapes, end = self.parse_until_text(True, r"}")
+            else:
+                escapes = ""
+            text = text.replace("\r\n", "\n")
+            self.append_node(
+                parsetree.Expression,
+                text,
+                escapes.strip(),
+                lineno=line,
+                pos=pos,
+            )
+            return True
+        else:
+            return False
+
+    def match_control_line(self):
+        match = self.match(
+            r"(?<=^)[\t ]*(%(?!%)|##)[\t ]*((?:(?:\\r?\n)|[^\r\n])*)"
+            r"(?:\r?\n|\Z)",
+            re.M,
+        )
+        if match:
+            operator = match.group(1)
+            text = match.group(2)
+            if operator == "%":
+                m2 = re.match(r"(end)?(\w+)\s*(.*)", text)
+                if not m2:
+                    raise exceptions.SyntaxException(
+                        "Invalid control line: '%s'" % text,
+                        **self.exception_kwargs
+                    )
+                isend, keyword = m2.group(1, 2)
+                isend = isend is not None
+
+                if isend:
+                    if not len(self.control_line):
+                        raise exceptions.SyntaxException(
+                            "No starting keyword '%s' for '%s'"
+                            % (keyword, text),
+                            **self.exception_kwargs
+                        )
+                    elif self.control_line[-1].keyword != keyword:
+                        raise exceptions.SyntaxException(
+                            "Keyword '%s' doesn't match keyword '%s'"
+                            % (text, self.control_line[-1].keyword),
+                            **self.exception_kwargs
+                        )
+                self.append_node(parsetree.ControlLine, keyword, isend, text)
+            else:
+                self.append_node(parsetree.Comment, text)
+            return True
+        else:
+            return False
+
+    def match_comment(self):
+        """matches the multiline version of a comment"""
+        match = self.match(r"<%doc>(.*?)</%doc>", re.S)
+        if match:
+            self.append_node(parsetree.Comment, match.group(1))
+            return True
+        else:
+            return False
diff --git a/third_party/python/Mako/mako/lookup.py b/third_party/python/Mako/mako/lookup.py
new file mode 100644
index 0000000000..476326d4d2
--- /dev/null
+++ b/third_party/python/Mako/mako/lookup.py
@@ -0,0 +1,372 @@
+# mako/lookup.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+import os
+import posixpath
+import re
+import stat
+
+from mako import exceptions
+from mako import util
+from mako.template import Template
+
+try:
+    import threading
+except:
+    import dummy_threading as threading
+
+
+class TemplateCollection(object):
+
+    """Represent a collection of :class:`.Template` objects,
+    identifiable via URI.
+
+    A :class:`.TemplateCollection` is linked to the usage of
+    all template tags that address other templates, such
+    as ``<%include>``, ``<%namespace>``, and ``<%inherit>``.
+    The ``file`` attribute of each of those tags refers
+    to a string URI that is passed to that :class:`.Template`
+    object's :class:`.TemplateCollection` for resolution.
+
+    :class:`.TemplateCollection` is an abstract class,
+    with the usual default implementation being :class:`.TemplateLookup`.
+
+     """
+
+    def has_template(self, uri):
+        """Return ``True`` if this :class:`.TemplateLookup` is
+        capable of returning a :class:`.Template` object for the
+        given ``uri``.
+
+        :param uri: String URI of the template to be resolved.
+
+        """
+        try:
+            self.get_template(uri)
+            return True
+        except exceptions.TemplateLookupException:
+            return False
+
+    def get_template(self, uri, relativeto=None):
+        """Return a :class:`.Template` object corresponding to the given
+        ``uri``.
+
+        The default implementation raises
+        :class:`.NotImplementedError`. Implementations should
+        raise :class:`.TemplateLookupException` if the given ``uri``
+        cannot be resolved.
+
+        :param uri: String URI of the template to be resolved.
+        :param relativeto: if present, the given ``uri`` is assumed to
+         be relative to this URI.
+
+        """
+        raise NotImplementedError()
+
+    def filename_to_uri(self, uri, filename):
+        """Convert the given ``filename`` to a URI relative to
+           this :class:`.TemplateCollection`."""
+
+        return uri
+
+    def adjust_uri(self, uri, filename):
+        """Adjust the given ``uri`` based on the calling ``filename``.
+
+        When this method is called from the runtime, the
+        ``filename`` parameter is taken directly to the ``filename``
+        attribute of the calling template. Therefore a custom
+        :class:`.TemplateCollection` subclass can place any string
+        identifier desired in the ``filename`` parameter of the
+        :class:`.Template` objects it constructs and have them come back
+        here.
+
+        """
+        return uri
+
+
+class TemplateLookup(TemplateCollection):
+
+    """Represent a collection of templates that locates template source files
+    from the local filesystem.
+
+    The primary argument is the ``directories`` argument, the list of
+    directories to search:
+
+    .. sourcecode:: python
+
+        lookup = TemplateLookup(["/path/to/templates"])
+        some_template = lookup.get_template("/index.html")
+
+    The :class:`.TemplateLookup` can also be given :class:`.Template` objects
+    programatically using :meth:`.put_string` or :meth:`.put_template`:
+
+    .. sourcecode:: python
+
+        lookup = TemplateLookup()
+        lookup.put_string("base.html", '''
+            <html><body>${self.next()}</body></html>
+        ''')
+        lookup.put_string("hello.html", '''
+            <%include file='base.html'/>
+
+            Hello, world !
+        ''')
+
+
+    :param directories: A list of directory names which will be
+     searched for a particular template URI. The URI is appended
+     to each directory and the filesystem checked.
+
+    :param collection_size: Approximate size of the collection used
+     to store templates. If left at its default of ``-1``, the size
+     is unbounded, and a plain Python dictionary is used to
+     relate URI strings to :class:`.Template` instances.
+     Otherwise, a least-recently-used cache object is used which
+     will maintain the size of the collection approximately to
+     the number given.
+
+    :param filesystem_checks: When at its default value of ``True``,
+     each call to :meth:`.TemplateLookup.get_template()` will
+     compare the filesystem last modified time to the time in
+     which an existing :class:`.Template` object was created.
+     This allows the :class:`.TemplateLookup` to regenerate a
+     new :class:`.Template` whenever the original source has
+     been updated. Set this to ``False`` for a very minor
+     performance increase.
+
+    :param modulename_callable: A callable which, when present,
+     is passed the path of the source file as well as the
+     requested URI, and then returns the full path of the
+     generated Python module file. This is used to inject
+     alternate schemes for Python module location. If left at
+     its default of ``None``, the built in system of generation
+     based on ``module_directory`` plus ``uri`` is used.
+
+    All other keyword parameters available for
+    :class:`.Template` are mirrored here. When new
+    :class:`.Template` objects are created, the keywords
+    established with this :class:`.TemplateLookup` are passed on
+    to each new :class:`.Template`.
+
+    """
+
+    def __init__(
+        self,
+        directories=None,
+        module_directory=None,
+        filesystem_checks=True,
+        collection_size=-1,
+        format_exceptions=False,
+        error_handler=None,
+        disable_unicode=False,
+        bytestring_passthrough=False,
+        output_encoding=None,
+        encoding_errors="strict",
+        cache_args=None,
+        cache_impl="beaker",
+        cache_enabled=True,
+        cache_type=None,
+        cache_dir=None,
+        cache_url=None,
+        modulename_callable=None,
+        module_writer=None,
+        default_filters=None,
+        buffer_filters=(),
+        strict_undefined=False,
+        imports=None,
+        future_imports=None,
+        enable_loop=True,
+        input_encoding=None,
+        preprocessor=None,
+        lexer_cls=None,
+        include_error_handler=None,
+    ):
+
+        self.directories = [
+            posixpath.normpath(d) for d in util.to_list(directories, ())
+        ]
+        self.module_directory = module_directory
+        self.modulename_callable = modulename_callable
+        self.filesystem_checks = filesystem_checks
+        self.collection_size = collection_size
+
+        if cache_args is None:
+            cache_args = {}
+        # transfer deprecated cache_* args
+        if cache_dir:
+            cache_args.setdefault("dir", cache_dir)
+        if cache_url:
+            cache_args.setdefault("url", cache_url)
+        if cache_type:
+            cache_args.setdefault("type", cache_type)
+
+        self.template_args = {
+            "format_exceptions": format_exceptions,
+            "error_handler": error_handler,
+            "include_error_handler": include_error_handler,
+            "disable_unicode": disable_unicode,
+            "bytestring_passthrough": bytestring_passthrough,
+            "output_encoding": output_encoding,
+            "cache_impl": cache_impl,
+            "encoding_errors": encoding_errors,
+            "input_encoding": input_encoding,
+            "module_directory": module_directory,
+            "module_writer": module_writer,
+            "cache_args": cache_args,
+            "cache_enabled": cache_enabled,
+            "default_filters": default_filters,
+            "buffer_filters": buffer_filters,
+            "strict_undefined": strict_undefined,
+            "imports": imports,
+            "future_imports": future_imports,
+            "enable_loop": enable_loop,
+            "preprocessor": preprocessor,
+            "lexer_cls": lexer_cls,
+        }
+
+        if collection_size == -1:
+            self._collection = {}
+            self._uri_cache = {}
+        else:
+            self._collection = util.LRUCache(collection_size)
+            self._uri_cache = util.LRUCache(collection_size)
+        self._mutex = threading.Lock()
+
+    def get_template(self, uri):
+        """Return a :class:`.Template` object corresponding to the given
+        ``uri``.
+
+        .. note:: The ``relativeto`` argument is not supported here at
+           the moment.
+
+        """
+
+        try:
+            if self.filesystem_checks:
+                return self._check(uri, self._collection[uri])
+            else:
+                return self._collection[uri]
+        except KeyError:
+            u = re.sub(r"^\/+", "", uri)
+            for dir_ in self.directories:
+                # make sure the path seperators are posix - os.altsep is empty
+                # on POSIX and cannot be used.
+                dir_ = dir_.replace(os.path.sep, posixpath.sep)
+                srcfile = posixpath.normpath(posixpath.join(dir_, u))
+                if os.path.isfile(srcfile):
+                    return self._load(srcfile, uri)
+            else:
+                raise exceptions.TopLevelLookupException(
+                    "Cant locate template for uri %r" % uri
+                )
+
+    def adjust_uri(self, uri, relativeto):
+        """Adjust the given ``uri`` based on the given relative URI."""
+
+        key = (uri, relativeto)
+        if key in self._uri_cache:
+            return self._uri_cache[key]
+
+        if uri[0] != "/":
+            if relativeto is not None:
+                v = self._uri_cache[key] = posixpath.join(
+                    posixpath.dirname(relativeto), uri
+                )
+            else:
+                v = self._uri_cache[key] = "/" + uri
+        else:
+            v = self._uri_cache[key] = uri
+        return v
+
+    def filename_to_uri(self, filename):
+        """Convert the given ``filename`` to a URI relative to
+           this :class:`.TemplateCollection`."""
+
+        try:
+            return self._uri_cache[filename]
+        except KeyError:
+            value = self._relativeize(filename)
+            self._uri_cache[filename] = value
+            return value
+
+    def _relativeize(self, filename):
+        """Return the portion of a filename that is 'relative'
+           to the directories in this lookup.
+
+        """
+
+        filename = posixpath.normpath(filename)
+        for dir_ in self.directories:
+            if filename[0 : len(dir_)] == dir_:
+                return filename[len(dir_) :]
+        else:
+            return None
+
+    def _load(self, filename, uri):
+        self._mutex.acquire()
+        try:
+            try:
+                # try returning from collection one
+                # more time in case concurrent thread already loaded
+                return self._collection[uri]
+            except KeyError:
+                pass
+            try:
+                if self.modulename_callable is not None:
+                    module_filename = self.modulename_callable(filename, uri)
+                else:
+                    module_filename = None
+                self._collection[uri] = template = Template(
+                    uri=uri,
+                    filename=posixpath.normpath(filename),
+                    lookup=self,
+                    module_filename=module_filename,
+                    **self.template_args
+                )
+                return template
+            except:
+                # if compilation fails etc, ensure
+                # template is removed from collection,
+                # re-raise
+                self._collection.pop(uri, None)
+                raise
+        finally:
+            self._mutex.release()
+
+    def _check(self, uri, template):
+        if template.filename is None:
+            return template
+
+        try:
+            template_stat = os.stat(template.filename)
+            if template.module._modified_time < template_stat[stat.ST_MTIME]:
+                self._collection.pop(uri, None)
+                return self._load(template.filename, uri)
+            else:
+                return template
+        except OSError:
+            self._collection.pop(uri, None)
+            raise exceptions.TemplateLookupException(
+                "Cant locate template for uri %r" % uri
+            )
+
+    def put_string(self, uri, text):
+        """Place a new :class:`.Template` object into this
+        :class:`.TemplateLookup`, based on the given string of
+        ``text``.
+
+        """
+        self._collection[uri] = Template(
+            text, lookup=self, uri=uri, **self.template_args
+        )
+
+    def put_template(self, uri, template):
+        """Place a new :class:`.Template` object into this
+        :class:`.TemplateLookup`, based on the given
+        :class:`.Template` object.
+
+        """
+        self._collection[uri] = template
diff --git a/third_party/python/Mako/mako/parsetree.py b/third_party/python/Mako/mako/parsetree.py
new file mode 100644
index 0000000000..801e48a7f4
--- /dev/null
+++ b/third_party/python/Mako/mako/parsetree.py
@@ -0,0 +1,665 @@
+# mako/parsetree.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""defines the parse tree components for Mako templates."""
+
+import re
+
+from mako import ast
+from mako import compat
+from mako import exceptions
+from mako import filters
+from mako import util
+
+
+class Node(object):
+
+    """base class for a Node in the parse tree."""
+
+    def __init__(self, source, lineno, pos, filename):
+        self.source = source
+        self.lineno = lineno
+        self.pos = pos
+        self.filename = filename
+
+    @property
+    def exception_kwargs(self):
+        return {
+            "source": self.source,
+            "lineno": self.lineno,
+            "pos": self.pos,
+            "filename": self.filename,
+        }
+
+    def get_children(self):
+        return []
+
+    def accept_visitor(self, visitor):
+        def traverse(node):
+            for n in node.get_children():
+                n.accept_visitor(visitor)
+
+        method = getattr(visitor, "visit" + self.__class__.__name__, traverse)
+        method(self)
+
+
+class TemplateNode(Node):
+
+    """a 'container' node that stores the overall collection of nodes."""
+
+    def __init__(self, filename):
+        super(TemplateNode, self).__init__("", 0, 0, filename)
+        self.nodes = []
+        self.page_attributes = {}
+
+    def get_children(self):
+        return self.nodes
+
+    def __repr__(self):
+        return "TemplateNode(%s, %r)" % (
+            util.sorted_dict_repr(self.page_attributes),
+            self.nodes,
+        )
+
+
+class ControlLine(Node):
+
+    """defines a control line, a line-oriented python line or end tag.
+
+    e.g.::
+
+        % if foo:
+            (markup)
+        % endif
+
+    """
+
+    has_loop_context = False
+
+    def __init__(self, keyword, isend, text, **kwargs):
+        super(ControlLine, self).__init__(**kwargs)
+        self.text = text
+        self.keyword = keyword
+        self.isend = isend
+        self.is_primary = keyword in ["for", "if", "while", "try", "with"]
+        self.nodes = []
+        if self.isend:
+            self._declared_identifiers = []
+            self._undeclared_identifiers = []
+        else:
+            code = ast.PythonFragment(text, **self.exception_kwargs)
+            self._declared_identifiers = code.declared_identifiers
+            self._undeclared_identifiers = code.undeclared_identifiers
+
+    def get_children(self):
+        return self.nodes
+
+    def declared_identifiers(self):
+        return self._declared_identifiers
+
+    def undeclared_identifiers(self):
+        return self._undeclared_identifiers
+
+    def is_ternary(self, keyword):
+        """return true if the given keyword is a ternary keyword
+        for this ControlLine"""
+
+        return keyword in {
+            "if": set(["else", "elif"]),
+            "try": set(["except", "finally"]),
+            "for": set(["else"]),
+        }.get(self.keyword, [])
+
+    def __repr__(self):
+        return "ControlLine(%r, %r, %r, %r)" % (
+            self.keyword,
+            self.text,
+            self.isend,
+            (self.lineno, self.pos),
+        )
+
+
+class Text(Node):
+
+    """defines plain text in the template."""
+
+    def __init__(self, content, **kwargs):
+        super(Text, self).__init__(**kwargs)
+        self.content = content
+
+    def __repr__(self):
+        return "Text(%r, %r)" % (self.content, (self.lineno, self.pos))
+
+
+class Code(Node):
+
+    """defines a Python code block, either inline or module level.
+
+    e.g.::
+
+        inline:
+        <%
+            x = 12
+        %>
+
+        module level:
+        <%!
+            import logger
+        %>
+
+    """
+
+    def __init__(self, text, ismodule, **kwargs):
+        super(Code, self).__init__(**kwargs)
+        self.text = text
+        self.ismodule = ismodule
+        self.code = ast.PythonCode(text, **self.exception_kwargs)
+
+    def declared_identifiers(self):
+        return self.code.declared_identifiers
+
+    def undeclared_identifiers(self):
+        return self.code.undeclared_identifiers
+
+    def __repr__(self):
+        return "Code(%r, %r, %r)" % (
+            self.text,
+            self.ismodule,
+            (self.lineno, self.pos),
+        )
+
+
+class Comment(Node):
+
+    """defines a comment line.
+
+    # this is a comment
+
+    """
+
+    def __init__(self, text, **kwargs):
+        super(Comment, self).__init__(**kwargs)
+        self.text = text
+
+    def __repr__(self):
+        return "Comment(%r, %r)" % (self.text, (self.lineno, self.pos))
+
+
+class Expression(Node):
+
+    """defines an inline expression.
+
+    ${x+y}
+
+    """
+
+    def __init__(self, text, escapes, **kwargs):
+        super(Expression, self).__init__(**kwargs)
+        self.text = text
+        self.escapes = escapes
+        self.escapes_code = ast.ArgumentList(escapes, **self.exception_kwargs)
+        self.code = ast.PythonCode(text, **self.exception_kwargs)
+
+    def declared_identifiers(self):
+        return []
+
+    def undeclared_identifiers(self):
+        # TODO: make the "filter" shortcut list configurable at parse/gen time
+        return self.code.undeclared_identifiers.union(
+            self.escapes_code.undeclared_identifiers.difference(
+                set(filters.DEFAULT_ESCAPES.keys())
+            )
+        ).difference(self.code.declared_identifiers)
+
+    def __repr__(self):
+        return "Expression(%r, %r, %r)" % (
+            self.text,
+            self.escapes_code.args,
+            (self.lineno, self.pos),
+        )
+
+
+class _TagMeta(type):
+
+    """metaclass to allow Tag to produce a subclass according to
+    its keyword"""
+
+    _classmap = {}
+
+    def __init__(cls, clsname, bases, dict_):
+        if getattr(cls, "__keyword__", None) is not None:
+            cls._classmap[cls.__keyword__] = cls
+        super(_TagMeta, cls).__init__(clsname, bases, dict_)
+
+    def __call__(cls, keyword, attributes, **kwargs):
+        if ":" in keyword:
+            ns, defname = keyword.split(":")
+            return type.__call__(
+                CallNamespaceTag, ns, defname, attributes, **kwargs
+            )
+
+        try:
+            cls = _TagMeta._classmap[keyword]
+        except KeyError:
+            raise exceptions.CompileException(
+                "No such tag: '%s'" % keyword,
+                source=kwargs["source"],
+                lineno=kwargs["lineno"],
+                pos=kwargs["pos"],
+                filename=kwargs["filename"],
+            )
+        return type.__call__(cls, keyword, attributes, **kwargs)
+
+
+class Tag(compat.with_metaclass(_TagMeta, Node)):
+    """abstract base class for tags.
+
+    e.g.::
+
+        <%sometag/>
+
+        <%someothertag>
+            stuff
+        </%someothertag>
+
+    """
+
+    __keyword__ = None
+
+    def __init__(
+        self,
+        keyword,
+        attributes,
+        expressions,
+        nonexpressions,
+        required,
+        **kwargs
+    ):
+        r"""construct a new Tag instance.
+
+        this constructor not called directly, and is only called
+        by subclasses.
+
+        :param keyword: the tag keyword
+
+        :param attributes: raw dictionary of attribute key/value pairs
+
+        :param expressions: a set of identifiers that are legal attributes,
+         which can also contain embedded expressions
+
+        :param nonexpressions: a set of identifiers that are legal
+         attributes, which cannot contain embedded expressions
+
+        :param \**kwargs:
+         other arguments passed to the Node superclass (lineno, pos)
+
+        """
+        super(Tag, self).__init__(**kwargs)
+        self.keyword = keyword
+        self.attributes = attributes
+        self._parse_attributes(expressions, nonexpressions)
+        missing = [r for r in required if r not in self.parsed_attributes]
+        if len(missing):
+            raise exceptions.CompileException(
+                "Missing attribute(s): %s"
+                % ",".join([repr(m) for m in missing]),
+                **self.exception_kwargs
+            )
+        self.parent = None
+        self.nodes = []
+
+    def is_root(self):
+        return self.parent is None
+
+    def get_children(self):
+        return self.nodes
+
+    def _parse_attributes(self, expressions, nonexpressions):
+        undeclared_identifiers = set()
+        self.parsed_attributes = {}
+        for key in self.attributes:
+            if key in expressions:
+                expr = []
+                for x in re.compile(r"(\${.+?})", re.S).split(
+                    self.attributes[key]
+                ):
+                    m = re.compile(r"^\${(.+?)}$", re.S).match(x)
+                    if m:
+                        code = ast.PythonCode(
+                            m.group(1).rstrip(), **self.exception_kwargs
+                        )
+                        # we aren't discarding "declared_identifiers" here,
+                        # which we do so that list comprehension-declared
+                        # variables aren't counted.   As yet can't find a
+                        # condition that requires it here.
+                        undeclared_identifiers = undeclared_identifiers.union(
+                            code.undeclared_identifiers
+                        )
+                        expr.append("(%s)" % m.group(1))
+                    else:
+                        if x:
+                            expr.append(repr(x))
+                self.parsed_attributes[key] = " + ".join(expr) or repr("")
+            elif key in nonexpressions:
+                if re.search(r"\${.+?}", self.attributes[key]):
+                    raise exceptions.CompileException(
+                        "Attibute '%s' in tag '%s' does not allow embedded "
+                        "expressions" % (key, self.keyword),
+                        **self.exception_kwargs
+                    )
+                self.parsed_attributes[key] = repr(self.attributes[key])
+            else:
+                raise exceptions.CompileException(
+                    "Invalid attribute for tag '%s': '%s'"
+                    % (self.keyword, key),
+                    **self.exception_kwargs
+                )
+        self.expression_undeclared_identifiers = undeclared_identifiers
+
+    def declared_identifiers(self):
+        return []
+
+    def undeclared_identifiers(self):
+        return self.expression_undeclared_identifiers
+
+    def __repr__(self):
+        return "%s(%r, %s, %r, %r)" % (
+            self.__class__.__name__,
+            self.keyword,
+            util.sorted_dict_repr(self.attributes),
+            (self.lineno, self.pos),
+            self.nodes,
+        )
+
+
+class IncludeTag(Tag):
+    __keyword__ = "include"
+
+    def __init__(self, keyword, attributes, **kwargs):
+        super(IncludeTag, self).__init__(
+            keyword,
+            attributes,
+            ("file", "import", "args"),
+            (),
+            ("file",),
+            **kwargs
+        )
+        self.page_args = ast.PythonCode(
+            "__DUMMY(%s)" % attributes.get("args", ""), **self.exception_kwargs
+        )
+
+    def declared_identifiers(self):
+        return []
+
+    def undeclared_identifiers(self):
+        identifiers = self.page_args.undeclared_identifiers.difference(
+            set(["__DUMMY"])
+        ).difference(self.page_args.declared_identifiers)
+        return identifiers.union(
+            super(IncludeTag, self).undeclared_identifiers()
+        )
+
+
+class NamespaceTag(Tag):
+    __keyword__ = "namespace"
+
+    def __init__(self, keyword, attributes, **kwargs):
+        super(NamespaceTag, self).__init__(
+            keyword,
+            attributes,
+            ("file",),
+            ("name", "inheritable", "import", "module"),
+            (),
+            **kwargs
+        )
+
+        self.name = attributes.get("name", "__anon_%s" % hex(abs(id(self))))
+        if "name" not in attributes and "import" not in attributes:
+            raise exceptions.CompileException(
+                "'name' and/or 'import' attributes are required "
+                "for <%namespace>",
+                **self.exception_kwargs
+            )
+        if "file" in attributes and "module" in attributes:
+            raise exceptions.CompileException(
+                "<%namespace> may only have one of 'file' or 'module'",
+                **self.exception_kwargs
+            )
+
+    def declared_identifiers(self):
+        return []
+
+
+class TextTag(Tag):
+    __keyword__ = "text"
+
+    def __init__(self, keyword, attributes, **kwargs):
+        super(TextTag, self).__init__(
+            keyword, attributes, (), ("filter"), (), **kwargs
+        )
+        self.filter_args = ast.ArgumentList(
+            attributes.get("filter", ""), **self.exception_kwargs
+        )
+
+    def undeclared_identifiers(self):
+        return self.filter_args.undeclared_identifiers.difference(
+            filters.DEFAULT_ESCAPES.keys()
+        ).union(self.expression_undeclared_identifiers)
+
+
+class DefTag(Tag):
+    __keyword__ = "def"
+
+    def __init__(self, keyword, attributes, **kwargs):
+        expressions = ["buffered", "cached"] + [
+            c for c in attributes if c.startswith("cache_")
+        ]
+
+        super(DefTag, self).__init__(
+            keyword,
+            attributes,
+            expressions,
+            ("name", "filter", "decorator"),
+            ("name",),
+            **kwargs
+        )
+        name = attributes["name"]
+        if re.match(r"^[\w_]+$", name):
+            raise exceptions.CompileException(
+                "Missing parenthesis in %def", **self.exception_kwargs
+            )
+        self.function_decl = ast.FunctionDecl(
+            "def " + name + ":pass", **self.exception_kwargs
+        )
+        self.name = self.function_decl.funcname
+        self.decorator = attributes.get("decorator", "")
+        self.filter_args = ast.ArgumentList(
+            attributes.get("filter", ""), **self.exception_kwargs
+        )
+
+    is_anonymous = False
+    is_block = False
+
+    @property
+    def funcname(self):
+        return self.function_decl.funcname
+
+    def get_argument_expressions(self, **kw):
+        return self.function_decl.get_argument_expressions(**kw)
+
+    def declared_identifiers(self):
+        return self.function_decl.allargnames
+
+    def undeclared_identifiers(self):
+        res = []
+        for c in self.function_decl.defaults:
+            res += list(
+                ast.PythonCode(
+                    c, **self.exception_kwargs
+                ).undeclared_identifiers
+            )
+        return (
+            set(res)
+            .union(
+                self.filter_args.undeclared_identifiers.difference(
+                    filters.DEFAULT_ESCAPES.keys()
+                )
+            )
+            .union(self.expression_undeclared_identifiers)
+            .difference(self.function_decl.allargnames)
+        )
+
+
+class BlockTag(Tag):
+    __keyword__ = "block"
+
+    def __init__(self, keyword, attributes, **kwargs):
+        expressions = ["buffered", "cached", "args"] + [
+            c for c in attributes if c.startswith("cache_")
+        ]
+
+        super(BlockTag, self).__init__(
+            keyword,
+            attributes,
+            expressions,
+            ("name", "filter", "decorator"),
+            (),
+            **kwargs
+        )
+        name = attributes.get("name")
+        if name and not re.match(r"^[\w_]+$", name):
+            raise exceptions.CompileException(
+                "%block may not specify an argument signature",
+                **self.exception_kwargs
+            )
+        if not name and attributes.get("args", None):
+            raise exceptions.CompileException(
+                "Only named %blocks may specify args", **self.exception_kwargs
+            )
+        self.body_decl = ast.FunctionArgs(
+            attributes.get("args", ""), **self.exception_kwargs
+        )
+
+        self.name = name
+        self.decorator = attributes.get("decorator", "")
+        self.filter_args = ast.ArgumentList(
+            attributes.get("filter", ""), **self.exception_kwargs
+        )
+
+    is_block = True
+
+    @property
+    def is_anonymous(self):
+        return self.name is None
+
+    @property
+    def funcname(self):
+        return self.name or "__M_anon_%d" % (self.lineno,)
+
+    def get_argument_expressions(self, **kw):
+        return self.body_decl.get_argument_expressions(**kw)
+
+    def declared_identifiers(self):
+        return self.body_decl.allargnames
+
+    def undeclared_identifiers(self):
+        return (
+            self.filter_args.undeclared_identifiers.difference(
+                filters.DEFAULT_ESCAPES.keys()
+            )
+        ).union(self.expression_undeclared_identifiers)
+
+
+class CallTag(Tag):
+    __keyword__ = "call"
+
+    def __init__(self, keyword, attributes, **kwargs):
+        super(CallTag, self).__init__(
+            keyword, attributes, ("args"), ("expr",), ("expr",), **kwargs
+        )
+        self.expression = attributes["expr"]
+        self.code = ast.PythonCode(self.expression, **self.exception_kwargs)
+        self.body_decl = ast.FunctionArgs(
+            attributes.get("args", ""), **self.exception_kwargs
+        )
+
+    def declared_identifiers(self):
+        return self.code.declared_identifiers.union(self.body_decl.allargnames)
+
+    def undeclared_identifiers(self):
+        return self.code.undeclared_identifiers.difference(
+            self.code.declared_identifiers
+        )
+
+
+class CallNamespaceTag(Tag):
+    def __init__(self, namespace, defname, attributes, **kwargs):
+        super(CallNamespaceTag, self).__init__(
+            namespace + ":" + defname,
+            attributes,
+            tuple(attributes.keys()) + ("args",),
+            (),
+            (),
+            **kwargs
+        )
+
+        self.expression = "%s.%s(%s)" % (
+            namespace,
+            defname,
+            ",".join(
+                [
+                    "%s=%s" % (k, v)
+                    for k, v in self.parsed_attributes.items()
+                    if k != "args"
+                ]
+            ),
+        )
+        self.code = ast.PythonCode(self.expression, **self.exception_kwargs)
+        self.body_decl = ast.FunctionArgs(
+            attributes.get("args", ""), **self.exception_kwargs
+        )
+
+    def declared_identifiers(self):
+        return self.code.declared_identifiers.union(self.body_decl.allargnames)
+
+    def undeclared_identifiers(self):
+        return self.code.undeclared_identifiers.difference(
+            self.code.declared_identifiers
+        )
+
+
+class InheritTag(Tag):
+    __keyword__ = "inherit"
+
+    def __init__(self, keyword, attributes, **kwargs):
+        super(InheritTag, self).__init__(
+            keyword, attributes, ("file",), (), ("file",), **kwargs
+        )
+
+
+class PageTag(Tag):
+    __keyword__ = "page"
+
+    def __init__(self, keyword, attributes, **kwargs):
+        expressions = [
+            "cached",
+            "args",
+            "expression_filter",
+            "enable_loop",
+        ] + [c for c in attributes if c.startswith("cache_")]
+
+        super(PageTag, self).__init__(
+            keyword, attributes, expressions, (), (), **kwargs
+        )
+        self.body_decl = ast.FunctionArgs(
+            attributes.get("args", ""), **self.exception_kwargs
+        )
+        self.filter_args = ast.ArgumentList(
+            attributes.get("expression_filter", ""), **self.exception_kwargs
+        )
+
+    def declared_identifiers(self):
+        return self.body_decl.allargnames
diff --git a/third_party/python/Mako/mako/pygen.py b/third_party/python/Mako/mako/pygen.py
new file mode 100644
index 0000000000..947721f1a5
--- /dev/null
+++ b/third_party/python/Mako/mako/pygen.py
@@ -0,0 +1,305 @@
+# mako/pygen.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""utilities for generating and formatting literal Python code."""
+
+import re
+
+from mako import exceptions
+
+
+class PythonPrinter(object):
+    def __init__(self, stream):
+        # indentation counter
+        self.indent = 0
+
+        # a stack storing information about why we incremented
+        # the indentation counter, to help us determine if we
+        # should decrement it
+        self.indent_detail = []
+
+        # the string of whitespace multiplied by the indent
+        # counter to produce a line
+        self.indentstring = "    "
+
+        # the stream we are writing to
+        self.stream = stream
+
+        # current line number
+        self.lineno = 1
+
+        # a list of lines that represents a buffered "block" of code,
+        # which can be later printed relative to an indent level
+        self.line_buffer = []
+
+        self.in_indent_lines = False
+
+        self._reset_multi_line_flags()
+
+        # mapping of generated python lines to template
+        # source lines
+        self.source_map = {}
+
+    def _update_lineno(self, num):
+        self.lineno += num
+
+    def start_source(self, lineno):
+        if self.lineno not in self.source_map:
+            self.source_map[self.lineno] = lineno
+
+    def write_blanks(self, num):
+        self.stream.write("\n" * num)
+        self._update_lineno(num)
+
+    def write_indented_block(self, block, starting_lineno=None):
+        """print a line or lines of python which already contain indentation.
+
+        The indentation of the total block of lines will be adjusted to that of
+        the current indent level."""
+        self.in_indent_lines = False
+        for i, l in enumerate(re.split(r"\r?\n", block)):
+            self.line_buffer.append(l)
+            if starting_lineno is not None:
+                self.start_source(starting_lineno + i)
+            self._update_lineno(1)
+
+    def writelines(self, *lines):
+        """print a series of lines of python."""
+        for line in lines:
+            self.writeline(line)
+
+    def writeline(self, line):
+        """print a line of python, indenting it according to the current
+        indent level.
+
+        this also adjusts the indentation counter according to the
+        content of the line.
+
+        """
+
+        if not self.in_indent_lines:
+            self._flush_adjusted_lines()
+            self.in_indent_lines = True
+
+        if (
+            line is None
+            or re.match(r"^\s*#", line)
+            or re.match(r"^\s*$", line)
+        ):
+            hastext = False
+        else:
+            hastext = True
+
+        is_comment = line and len(line) and line[0] == "#"
+
+        # see if this line should decrease the indentation level
+        if not is_comment and (not hastext or self._is_unindentor(line)):
+
+            if self.indent > 0:
+                self.indent -= 1
+                # if the indent_detail stack is empty, the user
+                # probably put extra closures - the resulting
+                # module wont compile.
+                if len(self.indent_detail) == 0:
+                    raise exceptions.SyntaxException(
+                        "Too many whitespace closures"
+                    )
+                self.indent_detail.pop()
+
+        if line is None:
+            return
+
+        # write the line
+        self.stream.write(self._indent_line(line) + "\n")
+        self._update_lineno(len(line.split("\n")))
+
+        # see if this line should increase the indentation level.
+        # note that a line can both decrase (before printing) and
+        # then increase (after printing) the indentation level.
+
+        if re.search(r":[ \t]*(?:#.*)?$", line):
+            # increment indentation count, and also
+            # keep track of what the keyword was that indented us,
+            # if it is a python compound statement keyword
+            # where we might have to look for an "unindent" keyword
+            match = re.match(r"^\s*(if|try|elif|while|for|with)", line)
+            if match:
+                # its a "compound" keyword, so we will check for "unindentors"
+                indentor = match.group(1)
+                self.indent += 1
+                self.indent_detail.append(indentor)
+            else:
+                indentor = None
+                # its not a "compound" keyword.  but lets also
+                # test for valid Python keywords that might be indenting us,
+                # else assume its a non-indenting line
+                m2 = re.match(
+                    r"^\s*(def|class|else|elif|except|finally)", line
+                )
+                if m2:
+                    self.indent += 1
+                    self.indent_detail.append(indentor)
+
+    def close(self):
+        """close this printer, flushing any remaining lines."""
+        self._flush_adjusted_lines()
+
+    def _is_unindentor(self, line):
+        """return true if the given line is an 'unindentor',
+        relative to the last 'indent' event received.
+
+        """
+
+        # no indentation detail has been pushed on; return False
+        if len(self.indent_detail) == 0:
+            return False
+
+        indentor = self.indent_detail[-1]
+
+        # the last indent keyword we grabbed is not a
+        # compound statement keyword; return False
+        if indentor is None:
+            return False
+
+        # if the current line doesnt have one of the "unindentor" keywords,
+        # return False
+        match = re.match(r"^\s*(else|elif|except|finally).*\:", line)
+        if not match:
+            return False
+
+        # whitespace matches up, we have a compound indentor,
+        # and this line has an unindentor, this
+        # is probably good enough
+        return True
+
+        # should we decide that its not good enough, heres
+        # more stuff to check.
+        # keyword = match.group(1)
+
+        # match the original indent keyword
+        # for crit in [
+        #   (r'if|elif', r'else|elif'),
+        #   (r'try', r'except|finally|else'),
+        #   (r'while|for', r'else'),
+        # ]:
+        #   if re.match(crit[0], indentor) and re.match(crit[1], keyword):
+        #        return True
+
+        # return False
+
+    def _indent_line(self, line, stripspace=""):
+        """indent the given line according to the current indent level.
+
+        stripspace is a string of space that will be truncated from the
+        start of the line before indenting."""
+
+        return re.sub(
+            r"^%s" % stripspace, self.indentstring * self.indent, line
+        )
+
+    def _reset_multi_line_flags(self):
+        """reset the flags which would indicate we are in a backslashed
+        or triple-quoted section."""
+
+        self.backslashed, self.triplequoted = False, False
+
+    def _in_multi_line(self, line):
+        """return true if the given line is part of a multi-line block,
+        via backslash or triple-quote."""
+
+        # we are only looking for explicitly joined lines here, not
+        # implicit ones (i.e. brackets, braces etc.).  this is just to
+        # guard against the possibility of modifying the space inside of
+        # a literal multiline string with unfortunately placed
+        # whitespace
+
+        current_state = self.backslashed or self.triplequoted
+
+        if re.search(r"\\$", line):
+            self.backslashed = True
+        else:
+            self.backslashed = False
+
+        triples = len(re.findall(r"\"\"\"|\'\'\'", line))
+        if triples == 1 or triples % 2 != 0:
+            self.triplequoted = not self.triplequoted
+
+        return current_state
+
+    def _flush_adjusted_lines(self):
+        stripspace = None
+        self._reset_multi_line_flags()
+
+        for entry in self.line_buffer:
+            if self._in_multi_line(entry):
+                self.stream.write(entry + "\n")
+            else:
+                entry = entry.expandtabs()
+                if stripspace is None and re.search(r"^[ \t]*[^# \t]", entry):
+                    stripspace = re.match(r"^([ \t]*)", entry).group(1)
+                self.stream.write(self._indent_line(entry, stripspace) + "\n")
+
+        self.line_buffer = []
+        self._reset_multi_line_flags()
+
+
+def adjust_whitespace(text):
+    """remove the left-whitespace margin of a block of Python code."""
+
+    state = [False, False]
+    (backslashed, triplequoted) = (0, 1)
+
+    def in_multi_line(line):
+        start_state = state[backslashed] or state[triplequoted]
+
+        if re.search(r"\\$", line):
+            state[backslashed] = True
+        else:
+            state[backslashed] = False
+
+        def match(reg, t):
+            m = re.match(reg, t)
+            if m:
+                return m, t[len(m.group(0)) :]
+            else:
+                return None, t
+
+        while line:
+            if state[triplequoted]:
+                m, line = match(r"%s" % state[triplequoted], line)
+                if m:
+                    state[triplequoted] = False
+                else:
+                    m, line = match(r".*?(?=%s|$)" % state[triplequoted], line)
+            else:
+                m, line = match(r"#", line)
+                if m:
+                    return start_state
+
+                m, line = match(r"\"\"\"|\'\'\'", line)
+                if m:
+                    state[triplequoted] = m.group(0)
+                    continue
+
+                m, line = match(r".*?(?=\"\"\"|\'\'\'|#|$)", line)
+
+        return start_state
+
+    def _indent_line(line, stripspace=""):
+        return re.sub(r"^%s" % stripspace, "", line)
+
+    lines = []
+    stripspace = None
+
+    for line in re.split(r"\r?\n", text):
+        if in_multi_line(line):
+            lines.append(line)
+        else:
+            line = line.expandtabs()
+            if stripspace is None and re.search(r"^[ \t]*[^# \t]", line):
+                stripspace = re.match(r"^([ \t]*)", line).group(1)
+            lines.append(_indent_line(line, stripspace))
+    return "\n".join(lines)
diff --git a/third_party/python/Mako/mako/pyparser.py b/third_party/python/Mako/mako/pyparser.py
new file mode 100644
index 0000000000..b16672d60c
--- /dev/null
+++ b/third_party/python/Mako/mako/pyparser.py
@@ -0,0 +1,242 @@
+# mako/pyparser.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""Handles parsing of Python code.
+
+Parsing to AST is done via _ast on Python > 2.5, otherwise the compiler
+module is used.
+"""
+
+import operator
+
+import _ast
+
+from mako import _ast_util
+from mako import compat
+from mako import exceptions
+from mako import util
+from mako.compat import arg_stringname
+
+if compat.py3k:
+    # words that cannot be assigned to (notably
+    # smaller than the total keys in __builtins__)
+    reserved = set(["True", "False", "None", "print"])
+
+    # the "id" attribute on a function node
+    arg_id = operator.attrgetter("arg")
+else:
+    # words that cannot be assigned to (notably
+    # smaller than the total keys in __builtins__)
+    reserved = set(["True", "False", "None"])
+
+    # the "id" attribute on a function node
+    arg_id = operator.attrgetter("id")
+
+util.restore__ast(_ast)
+
+
+def parse(code, mode="exec", **exception_kwargs):
+    """Parse an expression into AST"""
+
+    try:
+        return _ast_util.parse(code, "<unknown>", mode)
+    except Exception:
+        raise exceptions.SyntaxException(
+            "(%s) %s (%r)"
+            % (
+                compat.exception_as().__class__.__name__,
+                compat.exception_as(),
+                code[0:50],
+            ),
+            **exception_kwargs
+        )
+
+
+class FindIdentifiers(_ast_util.NodeVisitor):
+    def __init__(self, listener, **exception_kwargs):
+        self.in_function = False
+        self.in_assign_targets = False
+        self.local_ident_stack = set()
+        self.listener = listener
+        self.exception_kwargs = exception_kwargs
+
+    def _add_declared(self, name):
+        if not self.in_function:
+            self.listener.declared_identifiers.add(name)
+        else:
+            self.local_ident_stack.add(name)
+
+    def visit_ClassDef(self, node):
+        self._add_declared(node.name)
+
+    def visit_Assign(self, node):
+
+        # flip around the visiting of Assign so the expression gets
+        # evaluated first, in the case of a clause like "x=x+5" (x
+        # is undeclared)
+
+        self.visit(node.value)
+        in_a = self.in_assign_targets
+        self.in_assign_targets = True
+        for n in node.targets:
+            self.visit(n)
+        self.in_assign_targets = in_a
+
+    if compat.py3k:
+
+        # ExceptHandler is in Python 2, but this block only works in
+        # Python 3 (and is required there)
+
+        def visit_ExceptHandler(self, node):
+            if node.name is not None:
+                self._add_declared(node.name)
+            if node.type is not None:
+                self.visit(node.type)
+            for statement in node.body:
+                self.visit(statement)
+
+    def visit_Lambda(self, node, *args):
+        self._visit_function(node, True)
+
+    def visit_FunctionDef(self, node):
+        self._add_declared(node.name)
+        self._visit_function(node, False)
+
+    def _expand_tuples(self, args):
+        for arg in args:
+            if isinstance(arg, _ast.Tuple):
+                for n in arg.elts:
+                    yield n
+            else:
+                yield arg
+
+    def _visit_function(self, node, islambda):
+
+        # push function state onto stack.  dont log any more
+        # identifiers as "declared" until outside of the function,
+        # but keep logging identifiers as "undeclared". track
+        # argument names in each function header so they arent
+        # counted as "undeclared"
+
+        inf = self.in_function
+        self.in_function = True
+
+        local_ident_stack = self.local_ident_stack
+        self.local_ident_stack = local_ident_stack.union(
+            [arg_id(arg) for arg in self._expand_tuples(node.args.args)]
+        )
+        if islambda:
+            self.visit(node.body)
+        else:
+            for n in node.body:
+                self.visit(n)
+        self.in_function = inf
+        self.local_ident_stack = local_ident_stack
+
+    def visit_For(self, node):
+
+        # flip around visit
+
+        self.visit(node.iter)
+        self.visit(node.target)
+        for statement in node.body:
+            self.visit(statement)
+        for statement in node.orelse:
+            self.visit(statement)
+
+    def visit_Name(self, node):
+        if isinstance(node.ctx, _ast.Store):
+            # this is eqiuvalent to visit_AssName in
+            # compiler
+            self._add_declared(node.id)
+        elif (
+            node.id not in reserved
+            and node.id not in self.listener.declared_identifiers
+            and node.id not in self.local_ident_stack
+        ):
+            self.listener.undeclared_identifiers.add(node.id)
+
+    def visit_Import(self, node):
+        for name in node.names:
+            if name.asname is not None:
+                self._add_declared(name.asname)
+            else:
+                self._add_declared(name.name.split(".")[0])
+
+    def visit_ImportFrom(self, node):
+        for name in node.names:
+            if name.asname is not None:
+                self._add_declared(name.asname)
+            else:
+                if name.name == "*":
+                    raise exceptions.CompileException(
+                        "'import *' is not supported, since all identifier "
+                        "names must be explicitly declared.  Please use the "
+                        "form 'from <modulename> import <name1>, <name2>, "
+                        "...' instead.",
+                        **self.exception_kwargs
+                    )
+                self._add_declared(name.name)
+
+
+class FindTuple(_ast_util.NodeVisitor):
+    def __init__(self, listener, code_factory, **exception_kwargs):
+        self.listener = listener
+        self.exception_kwargs = exception_kwargs
+        self.code_factory = code_factory
+
+    def visit_Tuple(self, node):
+        for n in node.elts:
+            p = self.code_factory(n, **self.exception_kwargs)
+            self.listener.codeargs.append(p)
+            self.listener.args.append(ExpressionGenerator(n).value())
+            ldi = self.listener.declared_identifiers
+            self.listener.declared_identifiers = ldi.union(
+                p.declared_identifiers
+            )
+            lui = self.listener.undeclared_identifiers
+            self.listener.undeclared_identifiers = lui.union(
+                p.undeclared_identifiers
+            )
+
+
+class ParseFunc(_ast_util.NodeVisitor):
+    def __init__(self, listener, **exception_kwargs):
+        self.listener = listener
+        self.exception_kwargs = exception_kwargs
+
+    def visit_FunctionDef(self, node):
+        self.listener.funcname = node.name
+
+        argnames = [arg_id(arg) for arg in node.args.args]
+        if node.args.vararg:
+            argnames.append(arg_stringname(node.args.vararg))
+
+        if compat.py2k:
+            # kw-only args don't exist in Python 2
+            kwargnames = []
+        else:
+            kwargnames = [arg_id(arg) for arg in node.args.kwonlyargs]
+        if node.args.kwarg:
+            kwargnames.append(arg_stringname(node.args.kwarg))
+        self.listener.argnames = argnames
+        self.listener.defaults = node.args.defaults  # ast
+        self.listener.kwargnames = kwargnames
+        if compat.py2k:
+            self.listener.kwdefaults = []
+        else:
+            self.listener.kwdefaults = node.args.kw_defaults
+        self.listener.varargs = node.args.vararg
+        self.listener.kwargs = node.args.kwarg
+
+
+class ExpressionGenerator(object):
+    def __init__(self, astnode):
+        self.generator = _ast_util.SourceGenerator(" " * 4)
+        self.generator.visit(astnode)
+
+    def value(self):
+        return "".join(self.generator.result)
diff --git a/third_party/python/Mako/mako/runtime.py b/third_party/python/Mako/mako/runtime.py
new file mode 100644
index 0000000000..465908e6d8
--- /dev/null
+++ b/third_party/python/Mako/mako/runtime.py
@@ -0,0 +1,970 @@
+# mako/runtime.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""provides runtime services for templates, including Context,
+Namespace, and various helper functions."""
+
+import functools
+import sys
+
+from mako import compat
+from mako import exceptions
+from mako import util
+from mako.compat import compat_builtins
+
+
+class Context(object):
+
+    """Provides runtime namespace, output buffer, and various
+    callstacks for templates.
+
+    See :ref:`runtime_toplevel` for detail on the usage of
+    :class:`.Context`.
+
+     """
+
+    def __init__(self, buffer, **data):
+        self._buffer_stack = [buffer]
+
+        self._data = data
+
+        self._kwargs = data.copy()
+        self._with_template = None
+        self._outputting_as_unicode = None
+        self.namespaces = {}
+
+        # "capture" function which proxies to the
+        # generic "capture" function
+        self._data["capture"] = functools.partial(capture, self)
+
+        # "caller" stack used by def calls with content
+        self.caller_stack = self._data["caller"] = CallerStack()
+
+    def _set_with_template(self, t):
+        self._with_template = t
+        illegal_names = t.reserved_names.intersection(self._data)
+        if illegal_names:
+            raise exceptions.NameConflictError(
+                "Reserved words passed to render(): %s"
+                % ", ".join(illegal_names)
+            )
+
+    @property
+    def lookup(self):
+        """Return the :class:`.TemplateLookup` associated
+        with this :class:`.Context`.
+
+        """
+        return self._with_template.lookup
+
+    @property
+    def kwargs(self):
+        """Return the dictionary of top level keyword arguments associated
+        with this :class:`.Context`.
+
+        This dictionary only includes the top-level arguments passed to
+        :meth:`.Template.render`.  It does not include names produced within
+        the template execution such as local variable names or special names
+        such as ``self``, ``next``, etc.
+
+        The purpose of this dictionary is primarily for the case that
+        a :class:`.Template` accepts arguments via its ``<%page>`` tag,
+        which are normally expected to be passed via :meth:`.Template.render`,
+        except the template is being called in an inheritance context,
+        using the ``body()`` method.   :attr:`.Context.kwargs` can then be
+        used to propagate these arguments to the inheriting template::
+
+            ${next.body(**context.kwargs)}
+
+        """
+        return self._kwargs.copy()
+
+    def push_caller(self, caller):
+        """Push a ``caller`` callable onto the callstack for
+        this :class:`.Context`."""
+
+        self.caller_stack.append(caller)
+
+    def pop_caller(self):
+        """Pop a ``caller`` callable onto the callstack for this
+        :class:`.Context`."""
+
+        del self.caller_stack[-1]
+
+    def keys(self):
+        """Return a list of all names established in this :class:`.Context`."""
+
+        return list(self._data.keys())
+
+    def __getitem__(self, key):
+        if key in self._data:
+            return self._data[key]
+        else:
+            return compat_builtins.__dict__[key]
+
+    def _push_writer(self):
+        """push a capturing buffer onto this Context and return
+        the new writer function."""
+
+        buf = util.FastEncodingBuffer()
+        self._buffer_stack.append(buf)
+        return buf.write
+
+    def _pop_buffer_and_writer(self):
+        """pop the most recent capturing buffer from this Context
+        and return the current writer after the pop.
+
+        """
+
+        buf = self._buffer_stack.pop()
+        return buf, self._buffer_stack[-1].write
+
+    def _push_buffer(self):
+        """push a capturing buffer onto this Context."""
+
+        self._push_writer()
+
+    def _pop_buffer(self):
+        """pop the most recent capturing buffer from this Context."""
+
+        return self._buffer_stack.pop()
+
+    def get(self, key, default=None):
+        """Return a value from this :class:`.Context`."""
+
+        return self._data.get(key, compat_builtins.__dict__.get(key, default))
+
+    def write(self, string):
+        """Write a string to this :class:`.Context` object's
+        underlying output buffer."""
+
+        self._buffer_stack[-1].write(string)
+
+    def writer(self):
+        """Return the current writer function."""
+
+        return self._buffer_stack[-1].write
+
+    def _copy(self):
+        c = Context.__new__(Context)
+        c._buffer_stack = self._buffer_stack
+        c._data = self._data.copy()
+        c._kwargs = self._kwargs
+        c._with_template = self._with_template
+        c._outputting_as_unicode = self._outputting_as_unicode
+        c.namespaces = self.namespaces
+        c.caller_stack = self.caller_stack
+        return c
+
+    def _locals(self, d):
+        """Create a new :class:`.Context` with a copy of this
+        :class:`.Context`'s current state,
+        updated with the given dictionary.
+
+        The :attr:`.Context.kwargs` collection remains
+        unaffected.
+
+
+        """
+
+        if not d:
+            return self
+        c = self._copy()
+        c._data.update(d)
+        return c
+
+    def _clean_inheritance_tokens(self):
+        """create a new copy of this :class:`.Context`. with
+        tokens related to inheritance state removed."""
+
+        c = self._copy()
+        x = c._data
+        x.pop("self", None)
+        x.pop("parent", None)
+        x.pop("next", None)
+        return c
+
+
+class CallerStack(list):
+    def __init__(self):
+        self.nextcaller = None
+
+    def __nonzero__(self):
+        return self.__bool__()
+
+    def __bool__(self):
+        return len(self) and self._get_caller() and True or False
+
+    def _get_caller(self):
+        # this method can be removed once
+        # codegen MAGIC_NUMBER moves past 7
+        return self[-1]
+
+    def __getattr__(self, key):
+        return getattr(self._get_caller(), key)
+
+    def _push_frame(self):
+        frame = self.nextcaller or None
+        self.append(frame)
+        self.nextcaller = None
+        return frame
+
+    def _pop_frame(self):
+        self.nextcaller = self.pop()
+
+
+class Undefined(object):
+
+    """Represents an undefined value in a template.
+
+    All template modules have a constant value
+    ``UNDEFINED`` present which is an instance of this
+    object.
+
+    """
+
+    def __str__(self):
+        raise NameError("Undefined")
+
+    def __nonzero__(self):
+        return self.__bool__()
+
+    def __bool__(self):
+        return False
+
+
+UNDEFINED = Undefined()
+STOP_RENDERING = ""
+
+
+class LoopStack(object):
+
+    """a stack for LoopContexts that implements the context manager protocol
+    to automatically pop off the top of the stack on context exit
+    """
+
+    def __init__(self):
+        self.stack = []
+
+    def _enter(self, iterable):
+        self._push(iterable)
+        return self._top
+
+    def _exit(self):
+        self._pop()
+        return self._top
+
+    @property
+    def _top(self):
+        if self.stack:
+            return self.stack[-1]
+        else:
+            return self
+
+    def _pop(self):
+        return self.stack.pop()
+
+    def _push(self, iterable):
+        new = LoopContext(iterable)
+        if self.stack:
+            new.parent = self.stack[-1]
+        return self.stack.append(new)
+
+    def __getattr__(self, key):
+        raise exceptions.RuntimeException("No loop context is established")
+
+    def __iter__(self):
+        return iter(self._top)
+
+
+class LoopContext(object):
+
+    """A magic loop variable.
+    Automatically accessible in any ``% for`` block.
+
+    See the section :ref:`loop_context` for usage
+    notes.
+
+    :attr:`parent` -> :class:`.LoopContext` or ``None``
+        The parent loop, if one exists.
+    :attr:`index` -> `int`
+        The 0-based iteration count.
+    :attr:`reverse_index` -> `int`
+        The number of iterations remaining.
+    :attr:`first` -> `bool`
+        ``True`` on the first iteration, ``False`` otherwise.
+    :attr:`last` -> `bool`
+        ``True`` on the last iteration, ``False`` otherwise.
+    :attr:`even` -> `bool`
+        ``True`` when ``index`` is even.
+    :attr:`odd` -> `bool`
+        ``True`` when ``index`` is odd.
+    """
+
+    def __init__(self, iterable):
+        self._iterable = iterable
+        self.index = 0
+        self.parent = None
+
+    def __iter__(self):
+        for i in self._iterable:
+            yield i
+            self.index += 1
+
+    @util.memoized_instancemethod
+    def __len__(self):
+        return len(self._iterable)
+
+    @property
+    def reverse_index(self):
+        return len(self) - self.index - 1
+
+    @property
+    def first(self):
+        return self.index == 0
+
+    @property
+    def last(self):
+        return self.index == len(self) - 1
+
+    @property
+    def even(self):
+        return not self.odd
+
+    @property
+    def odd(self):
+        return bool(self.index % 2)
+
+    def cycle(self, *values):
+        """Cycle through values as the loop progresses.
+        """
+        if not values:
+            raise ValueError("You must provide values to cycle through")
+        return values[self.index % len(values)]
+
+
+class _NSAttr(object):
+    def __init__(self, parent):
+        self.__parent = parent
+
+    def __getattr__(self, key):
+        ns = self.__parent
+        while ns:
+            if hasattr(ns.module, key):
+                return getattr(ns.module, key)
+            else:
+                ns = ns.inherits
+        raise AttributeError(key)
+
+
+class Namespace(object):
+
+    """Provides access to collections of rendering methods, which
+      can be local, from other templates, or from imported modules.
+
+      To access a particular rendering method referenced by a
+      :class:`.Namespace`, use plain attribute access:
+
+      .. sourcecode:: mako
+
+        ${some_namespace.foo(x, y, z)}
+
+      :class:`.Namespace` also contains several built-in attributes
+      described here.
+
+      """
+
+    def __init__(
+        self,
+        name,
+        context,
+        callables=None,
+        inherits=None,
+        populate_self=True,
+        calling_uri=None,
+    ):
+        self.name = name
+        self.context = context
+        self.inherits = inherits
+        if callables is not None:
+            self.callables = dict([(c.__name__, c) for c in callables])
+
+    callables = ()
+
+    module = None
+    """The Python module referenced by this :class:`.Namespace`.
+
+    If the namespace references a :class:`.Template`, then
+    this module is the equivalent of ``template.module``,
+    i.e. the generated module for the template.
+
+    """
+
+    template = None
+    """The :class:`.Template` object referenced by this
+        :class:`.Namespace`, if any.
+
+    """
+
+    context = None
+    """The :class:`.Context` object for this :class:`.Namespace`.
+
+    Namespaces are often created with copies of contexts that
+    contain slightly different data, particularly in inheritance
+    scenarios. Using the :class:`.Context` off of a :class:`.Namespace` one
+    can traverse an entire chain of templates that inherit from
+    one-another.
+
+    """
+
+    filename = None
+    """The path of the filesystem file used for this
+    :class:`.Namespace`'s module or template.
+
+    If this is a pure module-based
+    :class:`.Namespace`, this evaluates to ``module.__file__``. If a
+    template-based namespace, it evaluates to the original
+    template file location.
+
+    """
+
+    uri = None
+    """The URI for this :class:`.Namespace`'s template.
+
+    I.e. whatever was sent to :meth:`.TemplateLookup.get_template()`.
+
+    This is the equivalent of :attr:`.Template.uri`.
+
+    """
+
+    _templateuri = None
+
+    @util.memoized_property
+    def attr(self):
+        """Access module level attributes by name.
+
+        This accessor allows templates to supply "scalar"
+        attributes which are particularly handy in inheritance
+        relationships.
+
+        .. seealso::
+
+            :ref:`inheritance_attr`
+
+            :ref:`namespace_attr_for_includes`
+
+        """
+        return _NSAttr(self)
+
+    def get_namespace(self, uri):
+        """Return a :class:`.Namespace` corresponding to the given ``uri``.
+
+        If the given ``uri`` is a relative URI (i.e. it does not
+        contain a leading slash ``/``), the ``uri`` is adjusted to
+        be relative to the ``uri`` of the namespace itself. This
+        method is therefore mostly useful off of the built-in
+        ``local`` namespace, described in :ref:`namespace_local`.
+
+        In
+        most cases, a template wouldn't need this function, and
+        should instead use the ``<%namespace>`` tag to load
+        namespaces. However, since all ``<%namespace>`` tags are
+        evaluated before the body of a template ever runs,
+        this method can be used to locate namespaces using
+        expressions that were generated within the body code of
+        the template, or to conditionally use a particular
+        namespace.
+
+        """
+        key = (self, uri)
+        if key in self.context.namespaces:
+            return self.context.namespaces[key]
+        else:
+            ns = TemplateNamespace(
+                uri,
+                self.context._copy(),
+                templateuri=uri,
+                calling_uri=self._templateuri,
+            )
+            self.context.namespaces[key] = ns
+            return ns
+
+    def get_template(self, uri):
+        """Return a :class:`.Template` from the given ``uri``.
+
+        The ``uri`` resolution is relative to the ``uri`` of this
+        :class:`.Namespace` object's :class:`.Template`.
+
+        """
+        return _lookup_template(self.context, uri, self._templateuri)
+
+    def get_cached(self, key, **kwargs):
+        """Return a value from the :class:`.Cache` referenced by this
+        :class:`.Namespace` object's :class:`.Template`.
+
+        The advantage to this method versus direct access to the
+        :class:`.Cache` is that the configuration parameters
+        declared in ``<%page>`` take effect here, thereby calling
+        up the same configured backend as that configured
+        by ``<%page>``.
+
+        """
+
+        return self.cache.get(key, **kwargs)
+
+    @property
+    def cache(self):
+        """Return the :class:`.Cache` object referenced
+        by this :class:`.Namespace` object's
+        :class:`.Template`.
+
+        """
+        return self.template.cache
+
+    def include_file(self, uri, **kwargs):
+        """Include a file at the given ``uri``."""
+
+        _include_file(self.context, uri, self._templateuri, **kwargs)
+
+    def _populate(self, d, l):
+        for ident in l:
+            if ident == "*":
+                for (k, v) in self._get_star():
+                    d[k] = v
+            else:
+                d[ident] = getattr(self, ident)
+
+    def _get_star(self):
+        if self.callables:
+            for key in self.callables:
+                yield (key, self.callables[key])
+
+    def __getattr__(self, key):
+        if key in self.callables:
+            val = self.callables[key]
+        elif self.inherits:
+            val = getattr(self.inherits, key)
+        else:
+            raise AttributeError(
+                "Namespace '%s' has no member '%s'" % (self.name, key)
+            )
+        setattr(self, key, val)
+        return val
+
+
+class TemplateNamespace(Namespace):
+
+    """A :class:`.Namespace` specific to a :class:`.Template` instance."""
+
+    def __init__(
+        self,
+        name,
+        context,
+        template=None,
+        templateuri=None,
+        callables=None,
+        inherits=None,
+        populate_self=True,
+        calling_uri=None,
+    ):
+        self.name = name
+        self.context = context
+        self.inherits = inherits
+        if callables is not None:
+            self.callables = dict([(c.__name__, c) for c in callables])
+
+        if templateuri is not None:
+            self.template = _lookup_template(context, templateuri, calling_uri)
+            self._templateuri = self.template.module._template_uri
+        elif template is not None:
+            self.template = template
+            self._templateuri = template.module._template_uri
+        else:
+            raise TypeError("'template' argument is required.")
+
+        if populate_self:
+            lclcallable, lclcontext = _populate_self_namespace(
+                context, self.template, self_ns=self
+            )
+
+    @property
+    def module(self):
+        """The Python module referenced by this :class:`.Namespace`.
+
+        If the namespace references a :class:`.Template`, then
+        this module is the equivalent of ``template.module``,
+        i.e. the generated module for the template.
+
+        """
+        return self.template.module
+
+    @property
+    def filename(self):
+        """The path of the filesystem file used for this
+        :class:`.Namespace`'s module or template.
+        """
+        return self.template.filename
+
+    @property
+    def uri(self):
+        """The URI for this :class:`.Namespace`'s template.
+
+        I.e. whatever was sent to :meth:`.TemplateLookup.get_template()`.
+
+        This is the equivalent of :attr:`.Template.uri`.
+
+        """
+        return self.template.uri
+
+    def _get_star(self):
+        if self.callables:
+            for key in self.callables:
+                yield (key, self.callables[key])
+
+        def get(key):
+            callable_ = self.template._get_def_callable(key)
+            return functools.partial(callable_, self.context)
+
+        for k in self.template.module._exports:
+            yield (k, get(k))
+
+    def __getattr__(self, key):
+        if key in self.callables:
+            val = self.callables[key]
+        elif self.template.has_def(key):
+            callable_ = self.template._get_def_callable(key)
+            val = functools.partial(callable_, self.context)
+        elif self.inherits:
+            val = getattr(self.inherits, key)
+
+        else:
+            raise AttributeError(
+                "Namespace '%s' has no member '%s'" % (self.name, key)
+            )
+        setattr(self, key, val)
+        return val
+
+
+class ModuleNamespace(Namespace):
+
+    """A :class:`.Namespace` specific to a Python module instance."""
+
+    def __init__(
+        self,
+        name,
+        context,
+        module,
+        callables=None,
+        inherits=None,
+        populate_self=True,
+        calling_uri=None,
+    ):
+        self.name = name
+        self.context = context
+        self.inherits = inherits
+        if callables is not None:
+            self.callables = dict([(c.__name__, c) for c in callables])
+
+        mod = __import__(module)
+        for token in module.split(".")[1:]:
+            mod = getattr(mod, token)
+        self.module = mod
+
+    @property
+    def filename(self):
+        """The path of the filesystem file used for this
+        :class:`.Namespace`'s module or template.
+        """
+        return self.module.__file__
+
+    def _get_star(self):
+        if self.callables:
+            for key in self.callables:
+                yield (key, self.callables[key])
+        for key in dir(self.module):
+            if key[0] != "_":
+                callable_ = getattr(self.module, key)
+                if callable(callable_):
+                    yield key, functools.partial(callable_, self.context)
+
+    def __getattr__(self, key):
+        if key in self.callables:
+            val = self.callables[key]
+        elif hasattr(self.module, key):
+            callable_ = getattr(self.module, key)
+            val = functools.partial(callable_, self.context)
+        elif self.inherits:
+            val = getattr(self.inherits, key)
+        else:
+            raise AttributeError(
+                "Namespace '%s' has no member '%s'" % (self.name, key)
+            )
+        setattr(self, key, val)
+        return val
+
+
+def supports_caller(func):
+    """Apply a caller_stack compatibility decorator to a plain
+    Python function.
+
+    See the example in :ref:`namespaces_python_modules`.
+
+    """
+
+    def wrap_stackframe(context, *args, **kwargs):
+        context.caller_stack._push_frame()
+        try:
+            return func(context, *args, **kwargs)
+        finally:
+            context.caller_stack._pop_frame()
+
+    return wrap_stackframe
+
+
+def capture(context, callable_, *args, **kwargs):
+    """Execute the given template def, capturing the output into
+    a buffer.
+
+    See the example in :ref:`namespaces_python_modules`.
+
+    """
+
+    if not callable(callable_):
+        raise exceptions.RuntimeException(
+            "capture() function expects a callable as "
+            "its argument (i.e. capture(func, *args, **kwargs))"
+        )
+    context._push_buffer()
+    try:
+        callable_(*args, **kwargs)
+    finally:
+        buf = context._pop_buffer()
+    return buf.getvalue()
+
+
+def _decorate_toplevel(fn):
+    def decorate_render(render_fn):
+        def go(context, *args, **kw):
+            def y(*args, **kw):
+                return render_fn(context, *args, **kw)
+
+            try:
+                y.__name__ = render_fn.__name__[7:]
+            except TypeError:
+                # < Python 2.4
+                pass
+            return fn(y)(context, *args, **kw)
+
+        return go
+
+    return decorate_render
+
+
+def _decorate_inline(context, fn):
+    def decorate_render(render_fn):
+        dec = fn(render_fn)
+
+        def go(*args, **kw):
+            return dec(context, *args, **kw)
+
+        return go
+
+    return decorate_render
+
+
+def _include_file(context, uri, calling_uri, **kwargs):
+    """locate the template from the given uri and include it in
+    the current output."""
+
+    template = _lookup_template(context, uri, calling_uri)
+    (callable_, ctx) = _populate_self_namespace(
+        context._clean_inheritance_tokens(), template
+    )
+    kwargs = _kwargs_for_include(callable_, context._data, **kwargs)
+    if template.include_error_handler:
+        try:
+            callable_(ctx, **kwargs)
+        except Exception:
+            result = template.include_error_handler(ctx, compat.exception_as())
+            if not result:
+                compat.reraise(*sys.exc_info())
+    else:
+        callable_(ctx, **kwargs)
+
+
+def _inherit_from(context, uri, calling_uri):
+    """called by the _inherit method in template modules to set
+    up the inheritance chain at the start of a template's
+    execution."""
+
+    if uri is None:
+        return None
+    template = _lookup_template(context, uri, calling_uri)
+    self_ns = context["self"]
+    ih = self_ns
+    while ih.inherits is not None:
+        ih = ih.inherits
+    lclcontext = context._locals({"next": ih})
+    ih.inherits = TemplateNamespace(
+        "self:%s" % template.uri,
+        lclcontext,
+        template=template,
+        populate_self=False,
+    )
+    context._data["parent"] = lclcontext._data["local"] = ih.inherits
+    callable_ = getattr(template.module, "_mako_inherit", None)
+    if callable_ is not None:
+        ret = callable_(template, lclcontext)
+        if ret:
+            return ret
+
+    gen_ns = getattr(template.module, "_mako_generate_namespaces", None)
+    if gen_ns is not None:
+        gen_ns(context)
+    return (template.callable_, lclcontext)
+
+
+def _lookup_template(context, uri, relativeto):
+    lookup = context._with_template.lookup
+    if lookup is None:
+        raise exceptions.TemplateLookupException(
+            "Template '%s' has no TemplateLookup associated"
+            % context._with_template.uri
+        )
+    uri = lookup.adjust_uri(uri, relativeto)
+    try:
+        return lookup.get_template(uri)
+    except exceptions.TopLevelLookupException:
+        raise exceptions.TemplateLookupException(str(compat.exception_as()))
+
+
+def _populate_self_namespace(context, template, self_ns=None):
+    if self_ns is None:
+        self_ns = TemplateNamespace(
+            "self:%s" % template.uri,
+            context,
+            template=template,
+            populate_self=False,
+        )
+    context._data["self"] = context._data["local"] = self_ns
+    if hasattr(template.module, "_mako_inherit"):
+        ret = template.module._mako_inherit(template, context)
+        if ret:
+            return ret
+    return (template.callable_, context)
+
+
+def _render(template, callable_, args, data, as_unicode=False):
+    """create a Context and return the string
+    output of the given template and template callable."""
+
+    if as_unicode:
+        buf = util.FastEncodingBuffer(as_unicode=True)
+    elif template.bytestring_passthrough:
+        buf = compat.StringIO()
+    else:
+        buf = util.FastEncodingBuffer(
+            as_unicode=as_unicode,
+            encoding=template.output_encoding,
+            errors=template.encoding_errors,
+        )
+    context = Context(buf, **data)
+    context._outputting_as_unicode = as_unicode
+    context._set_with_template(template)
+
+    _render_context(
+        template,
+        callable_,
+        context,
+        *args,
+        **_kwargs_for_callable(callable_, data)
+    )
+    return context._pop_buffer().getvalue()
+
+
+def _kwargs_for_callable(callable_, data):
+    argspec = compat.inspect_getargspec(callable_)
+    # for normal pages, **pageargs is usually present
+    if argspec[2]:
+        return data
+
+    # for rendering defs from the top level, figure out the args
+    namedargs = argspec[0] + [v for v in argspec[1:3] if v is not None]
+    kwargs = {}
+    for arg in namedargs:
+        if arg != "context" and arg in data and arg not in kwargs:
+            kwargs[arg] = data[arg]
+    return kwargs
+
+
+def _kwargs_for_include(callable_, data, **kwargs):
+    argspec = compat.inspect_getargspec(callable_)
+    namedargs = argspec[0] + [v for v in argspec[1:3] if v is not None]
+    for arg in namedargs:
+        if arg != "context" and arg in data and arg not in kwargs:
+            kwargs[arg] = data[arg]
+    return kwargs
+
+
+def _render_context(tmpl, callable_, context, *args, **kwargs):
+    import mako.template as template
+
+    # create polymorphic 'self' namespace for this
+    # template with possibly updated context
+    if not isinstance(tmpl, template.DefTemplate):
+        # if main render method, call from the base of the inheritance stack
+        (inherit, lclcontext) = _populate_self_namespace(context, tmpl)
+        _exec_template(inherit, lclcontext, args=args, kwargs=kwargs)
+    else:
+        # otherwise, call the actual rendering method specified
+        (inherit, lclcontext) = _populate_self_namespace(context, tmpl.parent)
+        _exec_template(callable_, context, args=args, kwargs=kwargs)
+
+
+def _exec_template(callable_, context, args=None, kwargs=None):
+    """execute a rendering callable given the callable, a
+    Context, and optional explicit arguments
+
+    the contextual Template will be located if it exists, and
+    the error handling options specified on that Template will
+    be interpreted here.
+    """
+    template = context._with_template
+    if template is not None and (
+        template.format_exceptions or template.error_handler
+    ):
+        try:
+            callable_(context, *args, **kwargs)
+        except Exception:
+            _render_error(template, context, compat.exception_as())
+        except:
+            e = sys.exc_info()[0]
+            _render_error(template, context, e)
+    else:
+        callable_(context, *args, **kwargs)
+
+
+def _render_error(template, context, error):
+    if template.error_handler:
+        result = template.error_handler(context, error)
+        if not result:
+            compat.reraise(*sys.exc_info())
+    else:
+        error_template = exceptions.html_error_template()
+        if context._outputting_as_unicode:
+            context._buffer_stack[:] = [
+                util.FastEncodingBuffer(as_unicode=True)
+            ]
+        else:
+            context._buffer_stack[:] = [
+                util.FastEncodingBuffer(
+                    error_template.output_encoding,
+                    error_template.encoding_errors,
+                )
+            ]
+
+        context._set_with_template(error_template)
+        error_template.render_context(context, error=error)
diff --git a/third_party/python/Mako/mako/template.py b/third_party/python/Mako/mako/template.py
new file mode 100644
index 0000000000..3fd08714b8
--- /dev/null
+++ b/third_party/python/Mako/mako/template.py
@@ -0,0 +1,780 @@
+# mako/template.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""Provides the Template class, a facade for parsing, generating and executing
+template strings, as well as template runtime operations."""
+
+import json
+import os
+import re
+import shutil
+import stat
+import sys
+import tempfile
+import types
+import weakref
+
+from mako import cache
+from mako import codegen
+from mako import compat
+from mako import exceptions
+from mako import runtime
+from mako import util
+from mako.lexer import Lexer
+
+
+class Template(object):
+
+    r"""Represents a compiled template.
+
+    :class:`.Template` includes a reference to the original
+    template source (via the :attr:`.source` attribute)
+    as well as the source code of the
+    generated Python module (i.e. the :attr:`.code` attribute),
+    as well as a reference to an actual Python module.
+
+    :class:`.Template` is constructed using either a literal string
+    representing the template text, or a filename representing a filesystem
+    path to a source file.
+
+    :param text: textual template source.  This argument is mutually
+     exclusive versus the ``filename`` parameter.
+
+    :param filename: filename of the source template.  This argument is
+     mutually exclusive versus the ``text`` parameter.
+
+    :param buffer_filters: string list of filters to be applied
+     to the output of ``%def``\ s which are buffered, cached, or otherwise
+     filtered, after all filters
+     defined with the ``%def`` itself have been applied. Allows the
+     creation of default expression filters that let the output
+     of return-valued ``%def``\ s "opt out" of that filtering via
+     passing special attributes or objects.
+
+    :param bytestring_passthrough: When ``True``, and ``output_encoding`` is
+     set to ``None``, and :meth:`.Template.render` is used to render,
+     the `StringIO` or `cStringIO` buffer will be used instead of the
+     default "fast" buffer.   This allows raw bytestrings in the
+     output stream, such as in expressions, to pass straight
+     through to the buffer.  This flag is forced
+     to ``True`` if ``disable_unicode`` is also configured.
+
+     .. versionadded:: 0.4
+        Added to provide the same behavior as that of the previous series.
+
+    :param cache_args: Dictionary of cache configuration arguments that
+     will be passed to the :class:`.CacheImpl`.   See :ref:`caching_toplevel`.
+
+    :param cache_dir:
+
+     .. deprecated:: 0.6
+        Use the ``'dir'`` argument in the ``cache_args`` dictionary.
+        See :ref:`caching_toplevel`.
+
+    :param cache_enabled: Boolean flag which enables caching of this
+     template.  See :ref:`caching_toplevel`.
+
+    :param cache_impl: String name of a :class:`.CacheImpl` caching
+     implementation to use.   Defaults to ``'beaker'``.
+
+    :param cache_type:
+
+     .. deprecated:: 0.6
+        Use the ``'type'`` argument in the ``cache_args`` dictionary.
+        See :ref:`caching_toplevel`.
+
+    :param cache_url:
+
+     .. deprecated:: 0.6
+        Use the ``'url'`` argument in the ``cache_args`` dictionary.
+        See :ref:`caching_toplevel`.
+
+    :param default_filters: List of string filter names that will
+     be applied to all expressions.  See :ref:`filtering_default_filters`.
+
+    :param disable_unicode: Disables all awareness of Python Unicode
+     objects.  See :ref:`unicode_disabled`.
+
+    :param enable_loop: When ``True``, enable the ``loop`` context variable.
+     This can be set to ``False`` to support templates that may
+     be making usage of the name "``loop``".   Individual templates can
+     re-enable the "loop" context by placing the directive
+     ``enable_loop="True"`` inside the ``<%page>`` tag -- see
+     :ref:`migrating_loop`.
+
+    :param encoding_errors: Error parameter passed to ``encode()`` when
+     string encoding is performed. See :ref:`usage_unicode`.
+
+    :param error_handler: Python callable which is called whenever
+     compile or runtime exceptions occur. The callable is passed
+     the current context as well as the exception. If the
+     callable returns ``True``, the exception is considered to
+     be handled, else it is re-raised after the function
+     completes. Is used to provide custom error-rendering
+     functions.
+
+     .. seealso::
+
+        :paramref:`.Template.include_error_handler` - include-specific
+        error handler function
+
+    :param format_exceptions: if ``True``, exceptions which occur during
+     the render phase of this template will be caught and
+     formatted into an HTML error page, which then becomes the
+     rendered result of the :meth:`.render` call. Otherwise,
+     runtime exceptions are propagated outwards.
+
+    :param imports: String list of Python statements, typically individual
+     "import" lines, which will be placed into the module level
+     preamble of all generated Python modules. See the example
+     in :ref:`filtering_default_filters`.
+
+    :param future_imports: String list of names to import from `__future__`.
+     These will be concatenated into a comma-separated string and inserted
+     into the beginning of the template, e.g. ``futures_imports=['FOO',
+     'BAR']`` results in ``from __future__ import FOO, BAR``.  If you're
+     interested in using features like the new division operator, you must
+     use future_imports to convey that to the renderer, as otherwise the
+     import will not appear as the first executed statement in the generated
+     code and will therefore not have the desired effect.
+
+    :param include_error_handler: An error handler that runs when this template
+     is included within another one via the ``<%include>`` tag, and raises an
+     error.  Compare to the :paramref:`.Template.error_handler` option.
+
+     .. versionadded:: 1.0.6
+
+     .. seealso::
+
+        :paramref:`.Template.error_handler` - top-level error handler function
+
+    :param input_encoding: Encoding of the template's source code.  Can
+     be used in lieu of the coding comment. See
+     :ref:`usage_unicode` as well as :ref:`unicode_toplevel` for
+     details on source encoding.
+
+    :param lookup: a :class:`.TemplateLookup` instance that will be used
+     for all file lookups via the ``<%namespace>``,
+     ``<%include>``, and ``<%inherit>`` tags. See
+     :ref:`usage_templatelookup`.
+
+    :param module_directory: Filesystem location where generated
+     Python module files will be placed.
+
+    :param module_filename: Overrides the filename of the generated
+     Python module file. For advanced usage only.
+
+    :param module_writer: A callable which overrides how the Python
+     module is written entirely.  The callable is passed the
+     encoded source content of the module and the destination
+     path to be written to.   The default behavior of module writing
+     uses a tempfile in conjunction with a file move in order
+     to make the operation atomic.   So a user-defined module
+     writing function that mimics the default behavior would be:
+
+     .. sourcecode:: python
+
+         import tempfile
+         import os
+         import shutil
+
+         def module_writer(source, outputpath):
+             (dest, name) = \\
+                 tempfile.mkstemp(
+                     dir=os.path.dirname(outputpath)
+                 )
+
+             os.write(dest, source)
+             os.close(dest)
+             shutil.move(name, outputpath)
+
+         from mako.template import Template
+         mytemplate = Template(
+                         filename="index.html",
+                         module_directory="/path/to/modules",
+                         module_writer=module_writer
+                     )
+
+     The function is provided for unusual configurations where
+     certain platform-specific permissions or other special
+     steps are needed.
+
+    :param output_encoding: The encoding to use when :meth:`.render`
+     is called.
+     See :ref:`usage_unicode` as well as :ref:`unicode_toplevel`.
+
+    :param preprocessor: Python callable which will be passed
+     the full template source before it is parsed. The return
+     result of the callable will be used as the template source
+     code.
+
+    :param lexer_cls: A :class:`.Lexer` class used to parse
+     the template.   The :class:`.Lexer` class is used by
+     default.
+
+     .. versionadded:: 0.7.4
+
+    :param strict_undefined: Replaces the automatic usage of
+     ``UNDEFINED`` for any undeclared variables not located in
+     the :class:`.Context` with an immediate raise of
+     ``NameError``. The advantage is immediate reporting of
+     missing variables which include the name.
+
+     .. versionadded:: 0.3.6
+
+    :param uri: string URI or other identifier for this template.
+     If not provided, the ``uri`` is generated from the filesystem
+     path, or from the in-memory identity of a non-file-based
+     template. The primary usage of the ``uri`` is to provide a key
+     within :class:`.TemplateLookup`, as well as to generate the
+     file path of the generated Python module file, if
+     ``module_directory`` is specified.
+
+    """
+
+    lexer_cls = Lexer
+
+    def __init__(
+        self,
+        text=None,
+        filename=None,
+        uri=None,
+        format_exceptions=False,
+        error_handler=None,
+        lookup=None,
+        output_encoding=None,
+        encoding_errors="strict",
+        module_directory=None,
+        cache_args=None,
+        cache_impl="beaker",
+        cache_enabled=True,
+        cache_type=None,
+        cache_dir=None,
+        cache_url=None,
+        module_filename=None,
+        input_encoding=None,
+        disable_unicode=False,
+        module_writer=None,
+        bytestring_passthrough=False,
+        default_filters=None,
+        buffer_filters=(),
+        strict_undefined=False,
+        imports=None,
+        future_imports=None,
+        enable_loop=True,
+        preprocessor=None,
+        lexer_cls=None,
+        include_error_handler=None,
+    ):
+        if uri:
+            self.module_id = re.sub(r"\W", "_", uri)
+            self.uri = uri
+        elif filename:
+            self.module_id = re.sub(r"\W", "_", filename)
+            drive, path = os.path.splitdrive(filename)
+            path = os.path.normpath(path).replace(os.path.sep, "/")
+            self.uri = path
+        else:
+            self.module_id = "memory:" + hex(id(self))
+            self.uri = self.module_id
+
+        u_norm = self.uri
+        if u_norm.startswith("/"):
+            u_norm = u_norm[1:]
+        u_norm = os.path.normpath(u_norm)
+        if u_norm.startswith(".."):
+            raise exceptions.TemplateLookupException(
+                'Template uri "%s" is invalid - '
+                "it cannot be relative outside "
+                "of the root path." % self.uri
+            )
+
+        self.input_encoding = input_encoding
+        self.output_encoding = output_encoding
+        self.encoding_errors = encoding_errors
+        self.disable_unicode = disable_unicode
+        self.bytestring_passthrough = bytestring_passthrough or disable_unicode
+        self.enable_loop = enable_loop
+        self.strict_undefined = strict_undefined
+        self.module_writer = module_writer
+
+        if compat.py3k and disable_unicode:
+            raise exceptions.UnsupportedError(
+                "Mako for Python 3 does not " "support disabling Unicode"
+            )
+        elif output_encoding and disable_unicode:
+            raise exceptions.UnsupportedError(
+                "output_encoding must be set to "
+                "None when disable_unicode is used."
+            )
+        if default_filters is None:
+            if compat.py3k or self.disable_unicode:
+                self.default_filters = ["str"]
+            else:
+                self.default_filters = ["unicode"]
+        else:
+            self.default_filters = default_filters
+        self.buffer_filters = buffer_filters
+
+        self.imports = imports
+        self.future_imports = future_imports
+        self.preprocessor = preprocessor
+
+        if lexer_cls is not None:
+            self.lexer_cls = lexer_cls
+
+        # if plain text, compile code in memory only
+        if text is not None:
+            (code, module) = _compile_text(self, text, filename)
+            self._code = code
+            self._source = text
+            ModuleInfo(module, None, self, filename, code, text, uri)
+        elif filename is not None:
+            # if template filename and a module directory, load
+            # a filesystem-based module file, generating if needed
+            if module_filename is not None:
+                path = module_filename
+            elif module_directory is not None:
+                path = os.path.abspath(
+                    os.path.join(
+                        os.path.normpath(module_directory), u_norm + ".py"
+                    )
+                )
+            else:
+                path = None
+            module = self._compile_from_file(path, filename)
+        else:
+            raise exceptions.RuntimeException(
+                "Template requires text or filename"
+            )
+
+        self.module = module
+        self.filename = filename
+        self.callable_ = self.module.render_body
+        self.format_exceptions = format_exceptions
+        self.error_handler = error_handler
+        self.include_error_handler = include_error_handler
+        self.lookup = lookup
+
+        self.module_directory = module_directory
+
+        self._setup_cache_args(
+            cache_impl,
+            cache_enabled,
+            cache_args,
+            cache_type,
+            cache_dir,
+            cache_url,
+        )
+
+    @util.memoized_property
+    def reserved_names(self):
+        if self.enable_loop:
+            return codegen.RESERVED_NAMES
+        else:
+            return codegen.RESERVED_NAMES.difference(["loop"])
+
+    def _setup_cache_args(
+        self,
+        cache_impl,
+        cache_enabled,
+        cache_args,
+        cache_type,
+        cache_dir,
+        cache_url,
+    ):
+        self.cache_impl = cache_impl
+        self.cache_enabled = cache_enabled
+        if cache_args:
+            self.cache_args = cache_args
+        else:
+            self.cache_args = {}
+
+        # transfer deprecated cache_* args
+        if cache_type:
+            self.cache_args["type"] = cache_type
+        if cache_dir:
+            self.cache_args["dir"] = cache_dir
+        if cache_url:
+            self.cache_args["url"] = cache_url
+
+    def _compile_from_file(self, path, filename):
+        if path is not None:
+            util.verify_directory(os.path.dirname(path))
+            filemtime = os.stat(filename)[stat.ST_MTIME]
+            if (
+                not os.path.exists(path)
+                or os.stat(path)[stat.ST_MTIME] < filemtime
+            ):
+                data = util.read_file(filename)
+                _compile_module_file(
+                    self, data, filename, path, self.module_writer
+                )
+            module = compat.load_module(self.module_id, path)
+            del sys.modules[self.module_id]
+            if module._magic_number != codegen.MAGIC_NUMBER:
+                data = util.read_file(filename)
+                _compile_module_file(
+                    self, data, filename, path, self.module_writer
+                )
+                module = compat.load_module(self.module_id, path)
+                del sys.modules[self.module_id]
+            ModuleInfo(module, path, self, filename, None, None, None)
+        else:
+            # template filename and no module directory, compile code
+            # in memory
+            data = util.read_file(filename)
+            code, module = _compile_text(self, data, filename)
+            self._source = None
+            self._code = code
+            ModuleInfo(module, None, self, filename, code, None, None)
+        return module
+
+    @property
+    def source(self):
+        """Return the template source code for this :class:`.Template`."""
+
+        return _get_module_info_from_callable(self.callable_).source
+
+    @property
+    def code(self):
+        """Return the module source code for this :class:`.Template`."""
+
+        return _get_module_info_from_callable(self.callable_).code
+
+    @util.memoized_property
+    def cache(self):
+        return cache.Cache(self)
+
+    @property
+    def cache_dir(self):
+        return self.cache_args["dir"]
+
+    @property
+    def cache_url(self):
+        return self.cache_args["url"]
+
+    @property
+    def cache_type(self):
+        return self.cache_args["type"]
+
+    def render(self, *args, **data):
+        """Render the output of this template as a string.
+
+        If the template specifies an output encoding, the string
+        will be encoded accordingly, else the output is raw (raw
+        output uses `cStringIO` and can't handle multibyte
+        characters). A :class:`.Context` object is created corresponding
+        to the given data. Arguments that are explicitly declared
+        by this template's internal rendering method are also
+        pulled from the given ``*args``, ``**data`` members.
+
+        """
+        return runtime._render(self, self.callable_, args, data)
+
+    def render_unicode(self, *args, **data):
+        """Render the output of this template as a unicode object."""
+
+        return runtime._render(
+            self, self.callable_, args, data, as_unicode=True
+        )
+
+    def render_context(self, context, *args, **kwargs):
+        """Render this :class:`.Template` with the given context.
+
+        The data is written to the context's buffer.
+
+        """
+        if getattr(context, "_with_template", None) is None:
+            context._set_with_template(self)
+        runtime._render_context(self, self.callable_, context, *args, **kwargs)
+
+    def has_def(self, name):
+        return hasattr(self.module, "render_%s" % name)
+
+    def get_def(self, name):
+        """Return a def of this template as a :class:`.DefTemplate`."""
+
+        return DefTemplate(self, getattr(self.module, "render_%s" % name))
+
+    def list_defs(self):
+        """return a list of defs in the template.
+
+        .. versionadded:: 1.0.4
+
+        """
+        return [i[7:] for i in dir(self.module) if i[:7] == "render_"]
+
+    def _get_def_callable(self, name):
+        return getattr(self.module, "render_%s" % name)
+
+    @property
+    def last_modified(self):
+        return self.module._modified_time
+
+
+class ModuleTemplate(Template):
+
+    """A Template which is constructed given an existing Python module.
+
+       e.g.::
+
+            t = Template("this is a template")
+            f = file("mymodule.py", "w")
+            f.write(t.code)
+            f.close()
+
+            import mymodule
+
+            t = ModuleTemplate(mymodule)
+            print(t.render())
+
+    """
+
+    def __init__(
+        self,
+        module,
+        module_filename=None,
+        template=None,
+        template_filename=None,
+        module_source=None,
+        template_source=None,
+        output_encoding=None,
+        encoding_errors="strict",
+        disable_unicode=False,
+        bytestring_passthrough=False,
+        format_exceptions=False,
+        error_handler=None,
+        lookup=None,
+        cache_args=None,
+        cache_impl="beaker",
+        cache_enabled=True,
+        cache_type=None,
+        cache_dir=None,
+        cache_url=None,
+        include_error_handler=None,
+    ):
+        self.module_id = re.sub(r"\W", "_", module._template_uri)
+        self.uri = module._template_uri
+        self.input_encoding = module._source_encoding
+        self.output_encoding = output_encoding
+        self.encoding_errors = encoding_errors
+        self.disable_unicode = disable_unicode
+        self.bytestring_passthrough = bytestring_passthrough or disable_unicode
+        self.enable_loop = module._enable_loop
+
+        if compat.py3k and disable_unicode:
+            raise exceptions.UnsupportedError(
+                "Mako for Python 3 does not " "support disabling Unicode"
+            )
+        elif output_encoding and disable_unicode:
+            raise exceptions.UnsupportedError(
+                "output_encoding must be set to "
+                "None when disable_unicode is used."
+            )
+
+        self.module = module
+        self.filename = template_filename
+        ModuleInfo(
+            module,
+            module_filename,
+            self,
+            template_filename,
+            module_source,
+            template_source,
+            module._template_uri,
+        )
+
+        self.callable_ = self.module.render_body
+        self.format_exceptions = format_exceptions
+        self.error_handler = error_handler
+        self.include_error_handler = include_error_handler
+        self.lookup = lookup
+        self._setup_cache_args(
+            cache_impl,
+            cache_enabled,
+            cache_args,
+            cache_type,
+            cache_dir,
+            cache_url,
+        )
+
+
+class DefTemplate(Template):
+
+    """A :class:`.Template` which represents a callable def in a parent
+    template."""
+
+    def __init__(self, parent, callable_):
+        self.parent = parent
+        self.callable_ = callable_
+        self.output_encoding = parent.output_encoding
+        self.module = parent.module
+        self.encoding_errors = parent.encoding_errors
+        self.format_exceptions = parent.format_exceptions
+        self.error_handler = parent.error_handler
+        self.include_error_handler = parent.include_error_handler
+        self.enable_loop = parent.enable_loop
+        self.lookup = parent.lookup
+        self.bytestring_passthrough = parent.bytestring_passthrough
+
+    def get_def(self, name):
+        return self.parent.get_def(name)
+
+
+class ModuleInfo(object):
+
+    """Stores information about a module currently loaded into
+    memory, provides reverse lookups of template source, module
+    source code based on a module's identifier.
+
+     """
+
+    _modules = weakref.WeakValueDictionary()
+
+    def __init__(
+        self,
+        module,
+        module_filename,
+        template,
+        template_filename,
+        module_source,
+        template_source,
+        template_uri,
+    ):
+        self.module = module
+        self.module_filename = module_filename
+        self.template_filename = template_filename
+        self.module_source = module_source
+        self.template_source = template_source
+        self.template_uri = template_uri
+        self._modules[module.__name__] = template._mmarker = self
+        if module_filename:
+            self._modules[module_filename] = self
+
+    @classmethod
+    def get_module_source_metadata(cls, module_source, full_line_map=False):
+        source_map = re.search(
+            r"__M_BEGIN_METADATA(.+?)__M_END_METADATA", module_source, re.S
+        ).group(1)
+        source_map = json.loads(source_map)
+        source_map["line_map"] = dict(
+            (int(k), int(v)) for k, v in source_map["line_map"].items()
+        )
+        if full_line_map:
+            f_line_map = source_map["full_line_map"] = []
+            line_map = source_map["line_map"]
+
+            curr_templ_line = 1
+            for mod_line in range(1, max(line_map)):
+                if mod_line in line_map:
+                    curr_templ_line = line_map[mod_line]
+                f_line_map.append(curr_templ_line)
+        return source_map
+
+    @property
+    def code(self):
+        if self.module_source is not None:
+            return self.module_source
+        else:
+            return util.read_python_file(self.module_filename)
+
+    @property
+    def source(self):
+        if self.template_source is not None:
+            if self.module._source_encoding and not isinstance(
+                self.template_source, compat.text_type
+            ):
+                return self.template_source.decode(
+                    self.module._source_encoding
+                )
+            else:
+                return self.template_source
+        else:
+            data = util.read_file(self.template_filename)
+            if self.module._source_encoding:
+                return data.decode(self.module._source_encoding)
+            else:
+                return data
+
+
+def _compile(template, text, filename, generate_magic_comment):
+    lexer = template.lexer_cls(
+        text,
+        filename,
+        disable_unicode=template.disable_unicode,
+        input_encoding=template.input_encoding,
+        preprocessor=template.preprocessor,
+    )
+    node = lexer.parse()
+    source = codegen.compile(
+        node,
+        template.uri,
+        filename,
+        default_filters=template.default_filters,
+        buffer_filters=template.buffer_filters,
+        imports=template.imports,
+        future_imports=template.future_imports,
+        source_encoding=lexer.encoding,
+        generate_magic_comment=generate_magic_comment,
+        disable_unicode=template.disable_unicode,
+        strict_undefined=template.strict_undefined,
+        enable_loop=template.enable_loop,
+        reserved_names=template.reserved_names,
+    )
+    return source, lexer
+
+
+def _compile_text(template, text, filename):
+    identifier = template.module_id
+    source, lexer = _compile(
+        template,
+        text,
+        filename,
+        generate_magic_comment=template.disable_unicode,
+    )
+
+    cid = identifier
+    if not compat.py3k and isinstance(cid, compat.text_type):
+        cid = cid.encode()
+    module = types.ModuleType(cid)
+    code = compile(source, cid, "exec")
+
+    # this exec() works for 2.4->3.3.
+    exec(code, module.__dict__, module.__dict__)
+    return (source, module)
+
+
+def _compile_module_file(template, text, filename, outputpath, module_writer):
+    source, lexer = _compile(
+        template, text, filename, generate_magic_comment=True
+    )
+
+    if isinstance(source, compat.text_type):
+        source = source.encode(lexer.encoding or "ascii")
+
+    if module_writer:
+        module_writer(source, outputpath)
+    else:
+        # make tempfiles in the same location as the ultimate
+        # location.   this ensures they're on the same filesystem,
+        # avoiding synchronization issues.
+        (dest, name) = tempfile.mkstemp(dir=os.path.dirname(outputpath))
+
+        os.write(dest, source)
+        os.close(dest)
+        shutil.move(name, outputpath)
+
+
+def _get_module_info_from_callable(callable_):
+    if compat.py3k:
+        return _get_module_info(callable_.__globals__["__name__"])
+    else:
+        return _get_module_info(callable_.func_globals["__name__"])
+
+
+def _get_module_info(filename):
+    return ModuleInfo._modules[filename]
diff --git a/third_party/python/Mako/mako/util.py b/third_party/python/Mako/mako/util.py
new file mode 100644
index 0000000000..16e3c72658
--- /dev/null
+++ b/third_party/python/Mako/mako/util.py
@@ -0,0 +1,400 @@
+# mako/util.py
+# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
+#
+# This module is part of Mako and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+from __future__ import absolute_import
+
+from ast import parse
+import codecs
+import collections
+import operator
+import os
+import re
+import timeit
+
+from mako import compat
+
+
+def update_wrapper(decorated, fn):
+    decorated.__wrapped__ = fn
+    decorated.__name__ = fn.__name__
+    return decorated
+
+
+class PluginLoader(object):
+    def __init__(self, group):
+        self.group = group
+        self.impls = {}
+
+    def load(self, name):
+        if name in self.impls:
+            return self.impls[name]()
+        else:
+            import pkg_resources
+
+            for impl in pkg_resources.iter_entry_points(self.group, name):
+                self.impls[name] = impl.load
+                return impl.load()
+            else:
+                from mako import exceptions
+
+                raise exceptions.RuntimeException(
+                    "Can't load plugin %s %s" % (self.group, name)
+                )
+
+    def register(self, name, modulepath, objname):
+        def load():
+            mod = __import__(modulepath)
+            for token in modulepath.split(".")[1:]:
+                mod = getattr(mod, token)
+            return getattr(mod, objname)
+
+        self.impls[name] = load
+
+
+def verify_directory(dir_):
+    """create and/or verify a filesystem directory."""
+
+    tries = 0
+
+    while not os.path.exists(dir_):
+        try:
+            tries += 1
+            os.makedirs(dir_, compat.octal("0775"))
+        except:
+            if tries > 5:
+                raise
+
+
+def to_list(x, default=None):
+    if x is None:
+        return default
+    if not isinstance(x, (list, tuple)):
+        return [x]
+    else:
+        return x
+
+
+class memoized_property(object):
+
+    """A read-only @property that is only evaluated once."""
+
+    def __init__(self, fget, doc=None):
+        self.fget = fget
+        self.__doc__ = doc or fget.__doc__
+        self.__name__ = fget.__name__
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            return self
+        obj.__dict__[self.__name__] = result = self.fget(obj)
+        return result
+
+
+class memoized_instancemethod(object):
+
+    """Decorate a method memoize its return value.
+
+    Best applied to no-arg methods: memoization is not sensitive to
+    argument values, and will always return the same value even when
+    called with different arguments.
+
+    """
+
+    def __init__(self, fget, doc=None):
+        self.fget = fget
+        self.__doc__ = doc or fget.__doc__
+        self.__name__ = fget.__name__
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            return self
+
+        def oneshot(*args, **kw):
+            result = self.fget(obj, *args, **kw)
+
+            def memo(*a, **kw):
+                return result
+
+            memo.__name__ = self.__name__
+            memo.__doc__ = self.__doc__
+            obj.__dict__[self.__name__] = memo
+            return result
+
+        oneshot.__name__ = self.__name__
+        oneshot.__doc__ = self.__doc__
+        return oneshot
+
+
+class SetLikeDict(dict):
+
+    """a dictionary that has some setlike methods on it"""
+
+    def union(self, other):
+        """produce a 'union' of this dict and another (at the key level).
+
+        values in the second dict take precedence over that of the first"""
+        x = SetLikeDict(**self)
+        x.update(other)
+        return x
+
+
+class FastEncodingBuffer(object):
+
+    """a very rudimentary buffer that is faster than StringIO,
+    but doesn't crash on unicode data like cStringIO."""
+
+    def __init__(self, encoding=None, errors="strict", as_unicode=False):
+        self.data = collections.deque()
+        self.encoding = encoding
+        if as_unicode:
+            self.delim = compat.u("")
+        else:
+            self.delim = ""
+        self.as_unicode = as_unicode
+        self.errors = errors
+        self.write = self.data.append
+
+    def truncate(self):
+        self.data = collections.deque()
+        self.write = self.data.append
+
+    def getvalue(self):
+        if self.encoding:
+            return self.delim.join(self.data).encode(
+                self.encoding, self.errors
+            )
+        else:
+            return self.delim.join(self.data)
+
+
+class LRUCache(dict):
+
+    """A dictionary-like object that stores a limited number of items,
+    discarding lesser used items periodically.
+
+    this is a rewrite of LRUCache from Myghty to use a periodic timestamp-based
+    paradigm so that synchronization is not really needed.  the size management
+    is inexact.
+    """
+
+    class _Item(object):
+        def __init__(self, key, value):
+            self.key = key
+            self.value = value
+            self.timestamp = timeit.default_timer()
+
+        def __repr__(self):
+            return repr(self.value)
+
+    def __init__(self, capacity, threshold=0.5):
+        self.capacity = capacity
+        self.threshold = threshold
+
+    def __getitem__(self, key):
+        item = dict.__getitem__(self, key)
+        item.timestamp = timeit.default_timer()
+        return item.value
+
+    def values(self):
+        return [i.value for i in dict.values(self)]
+
+    def setdefault(self, key, value):
+        if key in self:
+            return self[key]
+        else:
+            self[key] = value
+            return value
+
+    def __setitem__(self, key, value):
+        item = dict.get(self, key)
+        if item is None:
+            item = self._Item(key, value)
+            dict.__setitem__(self, key, item)
+        else:
+            item.value = value
+        self._manage_size()
+
+    def _manage_size(self):
+        while len(self) > self.capacity + self.capacity * self.threshold:
+            bytime = sorted(
+                dict.values(self),
+                key=operator.attrgetter("timestamp"),
+                reverse=True,
+            )
+            for item in bytime[self.capacity :]:
+                try:
+                    del self[item.key]
+                except KeyError:
+                    # if we couldn't find a key, most likely some other thread
+                    # broke in on us. loop around and try again
+                    break
+
+
+# Regexp to match python magic encoding line
+_PYTHON_MAGIC_COMMENT_re = re.compile(
+    r"[ \t\f]* \# .* coding[=:][ \t]*([-\w.]+)", re.VERBOSE
+)
+
+
+def parse_encoding(fp):
+    """Deduce the encoding of a Python source file (binary mode) from magic
+    comment.
+
+    It does this in the same way as the `Python interpreter`__
+
+    .. __: http://docs.python.org/ref/encodings.html
+
+    The ``fp`` argument should be a seekable file object in binary mode.
+    """
+    pos = fp.tell()
+    fp.seek(0)
+    try:
+        line1 = fp.readline()
+        has_bom = line1.startswith(codecs.BOM_UTF8)
+        if has_bom:
+            line1 = line1[len(codecs.BOM_UTF8) :]
+
+        m = _PYTHON_MAGIC_COMMENT_re.match(line1.decode("ascii", "ignore"))
+        if not m:
+            try:
+                parse(line1.decode("ascii", "ignore"))
+            except (ImportError, SyntaxError):
+                # Either it's a real syntax error, in which case the source
+                # is not valid python source, or line2 is a continuation of
+                # line1, in which case we don't want to scan line2 for a magic
+                # comment.
+                pass
+            else:
+                line2 = fp.readline()
+                m = _PYTHON_MAGIC_COMMENT_re.match(
+                    line2.decode("ascii", "ignore")
+                )
+
+        if has_bom:
+            if m:
+                raise SyntaxError(
+                    "python refuses to compile code with both a UTF8"
+                    " byte-order-mark and a magic encoding comment"
+                )
+            return "utf_8"
+        elif m:
+            return m.group(1)
+        else:
+            return None
+    finally:
+        fp.seek(pos)
+
+
+def sorted_dict_repr(d):
+    """repr() a dictionary with the keys in order.
+
+    Used by the lexer unit test to compare parse trees based on strings.
+
+    """
+    keys = list(d.keys())
+    keys.sort()
+    return "{" + ", ".join(["%r: %r" % (k, d[k]) for k in keys]) + "}"
+
+
+def restore__ast(_ast):
+    """Attempt to restore the required classes to the _ast module if it
+    appears to be missing them
+    """
+    if hasattr(_ast, "AST"):
+        return
+    _ast.PyCF_ONLY_AST = 2 << 9
+    m = compile(
+        """\
+def foo(): pass
+class Bar(object): pass
+if False: pass
+baz = 'mako'
+1 + 2 - 3 * 4 / 5
+6 // 7 % 8 << 9 >> 10
+11 & 12 ^ 13 | 14
+15 and 16 or 17
+-baz + (not +18) - ~17
+baz and 'foo' or 'bar'
+(mako is baz == baz) is not baz != mako
+mako > baz < mako >= baz <= mako
+mako in baz not in mako""",
+        "<unknown>",
+        "exec",
+        _ast.PyCF_ONLY_AST,
+    )
+    _ast.Module = type(m)
+
+    for cls in _ast.Module.__mro__:
+        if cls.__name__ == "mod":
+            _ast.mod = cls
+        elif cls.__name__ == "AST":
+            _ast.AST = cls
+
+    _ast.FunctionDef = type(m.body[0])
+    _ast.ClassDef = type(m.body[1])
+    _ast.If = type(m.body[2])
+
+    _ast.Name = type(m.body[3].targets[0])
+    _ast.Store = type(m.body[3].targets[0].ctx)
+    _ast.Str = type(m.body[3].value)
+
+    _ast.Sub = type(m.body[4].value.op)
+    _ast.Add = type(m.body[4].value.left.op)
+    _ast.Div = type(m.body[4].value.right.op)
+    _ast.Mult = type(m.body[4].value.right.left.op)
+
+    _ast.RShift = type(m.body[5].value.op)
+    _ast.LShift = type(m.body[5].value.left.op)
+    _ast.Mod = type(m.body[5].value.left.left.op)
+    _ast.FloorDiv = type(m.body[5].value.left.left.left.op)
+
+    _ast.BitOr = type(m.body[6].value.op)
+    _ast.BitXor = type(m.body[6].value.left.op)
+    _ast.BitAnd = type(m.body[6].value.left.left.op)
+
+    _ast.Or = type(m.body[7].value.op)
+    _ast.And = type(m.body[7].value.values[0].op)
+
+    _ast.Invert = type(m.body[8].value.right.op)
+    _ast.Not = type(m.body[8].value.left.right.op)
+    _ast.UAdd = type(m.body[8].value.left.right.operand.op)
+    _ast.USub = type(m.body[8].value.left.left.op)
+
+    _ast.Or = type(m.body[9].value.op)
+    _ast.And = type(m.body[9].value.values[0].op)
+
+    _ast.IsNot = type(m.body[10].value.ops[0])
+    _ast.NotEq = type(m.body[10].value.ops[1])
+    _ast.Is = type(m.body[10].value.left.ops[0])
+    _ast.Eq = type(m.body[10].value.left.ops[1])
+
+    _ast.Gt = type(m.body[11].value.ops[0])
+    _ast.Lt = type(m.body[11].value.ops[1])
+    _ast.GtE = type(m.body[11].value.ops[2])
+    _ast.LtE = type(m.body[11].value.ops[3])
+
+    _ast.In = type(m.body[12].value.ops[0])
+    _ast.NotIn = type(m.body[12].value.ops[1])
+
+
+def read_file(path, mode="rb"):
+    fp = open(path, mode)
+    try:
+        data = fp.read()
+        return data
+    finally:
+        fp.close()
+
+
+def read_python_file(path):
+    fp = open(path, "rb")
+    try:
+        encoding = parse_encoding(fp)
+        data = fp.read()
+        if encoding:
+            data = data.decode(encoding)
+        return data
+    finally:
+        fp.close()