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diff --git a/share/extensions/inkex/command.py b/share/extensions/inkex/command.py
new file mode 100644
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+++ b/share/extensions/inkex/command.py
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+# coding=utf-8
+#
+# Copyright (C) 2019 Martin Owens
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA.
+#
+"""
+This API provides methods for calling Inkscape to execute a given
+Inkscape command. This may be needed for various compiling options
+(e.g., png), running other extensions or performing other options only
+available via the shell API.
+
+Best practice is to avoid using this API except when absolutely necessary,
+since it is resource-intensive to invoke a new Inkscape instance.
+
+However, in any circumstance when it is necessary to call Inkscape, it
+is strongly recommended that you do so through this API, rather than calling
+it yourself, to take advantage of the security settings and testing functions.
+
+"""
+
+import os
+import sys
+from shutil import which as warlock
+
+from subprocess import Popen, PIPE
+from tempfile import TemporaryDirectory
+from typing import List
+from lxml.etree import ElementTree
+
+from .elements import SvgDocumentElement
+
+INKSCAPE_EXECUTABLE_NAME = os.environ.get("INKSCAPE_COMMAND")
+if INKSCAPE_EXECUTABLE_NAME is None:
+    if sys.platform == "win32":
+        # prefer inkscape.exe over inkscape.com which spawns a command window
+        INKSCAPE_EXECUTABLE_NAME = "inkscape.exe"
+    else:
+        INKSCAPE_EXECUTABLE_NAME = "inkscape"
+
+
+class CommandNotFound(IOError):
+    """Command is not found"""
+
+
+class ProgramRunError(ValueError):
+    """A specialized ValueError that is raised when a call to an external command fails.
+    It stores additional information about a failed call to an external program.
+
+    If only the ``program`` parameter is given, it is interpreted as the error message.
+    Otherwise, the error message is compiled from all constructor parameters."""
+
+    program: str
+    """The absolute path to the called executable"""
+
+    returncode: int
+    """Return code of the program call"""
+
+    stderr: str
+    """stderr stream output of the call"""
+
+    stdout: str
+    """stdout stream output of the call"""
+
+    arguments: List
+    """Arguments of the call"""
+
+    def __init__(self, program, returncode=None, stderr=None, stdout=None, args=None):
+        self.program = program
+        self.returncode = returncode
+        self.stderr = stderr
+        self.stdout = stdout
+        self.arguments = args
+        super().__init__(str(self))
+
+    def __str__(self):
+        if self.returncode is None:
+            return self.program
+        return (
+            f"Return Code: {self.returncode}: {self.stderr}\n{self.stdout}"
+            f"\nargs: {self.args}"
+        )
+
+
+def which(program):
+    """
+    Attempt different methods of trying to find if the program exists.
+    """
+    if os.path.isabs(program) and os.path.isfile(program):
+        return program
+    # On Windows, shutil.which may give preference to .py files in the current directory
+    # (such as pdflatex.py), e.g. if .PY is in pathext, because the current directory is
+    # prepended to PATH. This can be suppressed by explicitly appending the current
+    # directory.
+
+    try:
+        if sys.platform == "win32":
+            prog = warlock(program, path=os.environ["PATH"] + ";" + os.curdir)
+            if prog:
+                return prog
+    except ImportError:
+        pass
+
+    try:
+        # Python3 only version of which
+        prog = warlock(program)
+        if prog:
+            return prog
+    except ImportError:
+        pass  # python2
+
+    # There may be other methods for doing a `which` command for other
+    # operating systems; These should go here as they are discovered.
+
+    raise CommandNotFound(f"Can not find the command: '{program}'")
+
+
+def write_svg(svg, *filename):
+    """Writes an svg to the given filename"""
+    filename = os.path.join(*filename)
+    if os.path.isfile(filename):
+        return filename
+    with open(filename, "wb") as fhl:
+        if isinstance(svg, SvgDocumentElement):
+            svg = ElementTree(svg)
+        if hasattr(svg, "write"):
+            # XML document
+            svg.write(fhl)
+        elif isinstance(svg, bytes):
+            fhl.write(svg)
+        else:
+            raise ValueError("Not sure what type of SVG data this is.")
+    return filename
+
+
+def to_arg(arg, oldie=False):
+    """Convert a python argument to a command line argument"""
+    if isinstance(arg, (tuple, list)):
+        (arg, val) = arg
+        arg = "-" + arg
+        if len(arg) > 2 and not oldie:
+            arg = "-" + arg
+        if val is True:
+            return arg
+        if val is False:
+            return None
+        return f"{arg}={str(val)}"
+    return str(arg)
+
+
+def to_args(prog, *positionals, **arguments):
+    """Compile arguments and keyword arguments into a list of strings which Popen will
+    understand.
+
+    :param prog:
+        Program executable prepended to the output.
+    :type first: ``str``
+
+    :Arguments:
+        * (``str``) -- String added as given
+        * (``tuple``) -- Ordered version of Kwyward Arguments, see below
+
+    :Keyword Arguments:
+        * *name* (``str``) --
+          Becomes ``--name="val"``
+        * *name* (``bool``) --
+          Becomes ``--name``
+        * *name* (``list``) --
+          Becomes ``--name="val1"`` ...
+        * *n* (``str``) --
+          Becomes ``-n=val``
+        * *n* (``bool``) --
+          Becomes ``-n``
+
+    :return: Returns a list of compiled arguments ready for Popen.
+    :rtype: ``list[str]``
+    """
+    args = [prog]
+    oldie = arguments.pop("oldie", False)
+    for arg, value in arguments.items():
+        arg = arg.replace("_", "-").strip()
+
+        if isinstance(value, tuple):
+            value = list(value)
+        elif not isinstance(value, list):
+            value = [value]
+
+        for val in value:
+            args.append(to_arg((arg, val), oldie))
+
+    args += [to_arg(pos, oldie) for pos in positionals if pos is not None]
+    # Filter out empty non-arguments
+    return [arg for arg in args if arg is not None]
+
+
+def to_args_sorted(prog, *positionals, **arguments):
+    """same as :func:`to_args`, but keyword arguments are sorted beforehand
+
+    .. versionadded:: 1.2"""
+    return to_args(prog, *positionals, **dict(sorted(arguments.items())))
+
+
+def _call(program, *args, **kwargs):
+    stdin = kwargs.pop("stdin", None)
+    if isinstance(stdin, str):
+        stdin = stdin.encode("utf-8")
+    inpipe = PIPE if stdin else None
+
+    args = to_args(which(program), *args, **kwargs)
+
+    kwargs = {}
+    if sys.platform == "win32":
+        kwargs["creationflags"] = 0x08000000  # create no console window
+
+    with Popen(
+        args,
+        shell=False,  # Never have shell=True
+        stdin=inpipe,  # StdIn not used (yet)
+        stdout=PIPE,  # Grab any output (return it)
+        stderr=PIPE,  # Take all errors, just incase
+        **kwargs,
+    ) as process:
+        (stdout, stderr) = process.communicate(input=stdin)
+        if process.returncode == 0:
+            return stdout
+        raise ProgramRunError(program, process.returncode, stderr, stdout, args)
+
+
+def call(program, *args, **kwargs):
+    """
+    Generic caller to open any program and return its stdout::
+
+        stdout = call('executable', arg1, arg2, dash_dash_arg='foo', d=True, ...)
+
+    Will raise :class:`ProgramRunError` if return code is not 0.
+
+    Keyword arguments:
+        return_binary: Should stdout return raw bytes (default: False)
+
+            .. versionadded:: 1.1
+        stdin: The string or bytes containing the stdin (default: None)
+
+    All other arguments converted using :func:`to_args` function.
+    """
+    # We use this long input because it's less likely to conflict with --binary=
+    binary = kwargs.pop("return_binary", False)
+    stdout = _call(program, *args, **kwargs)
+    # Convert binary to string when we wish to have strings we do this here
+    # so the mock tests will also run the conversion (always returns bytes)
+    if not binary and isinstance(stdout, bytes):
+        return stdout.decode(sys.stdout.encoding or "utf-8")
+    return stdout
+
+
+def inkscape(svg_file, *args, **kwargs):
+    """
+    Call Inkscape with the given svg_file and the given arguments, see call()
+    """
+    return call(INKSCAPE_EXECUTABLE_NAME, svg_file, *args, **kwargs)
+
+
+def inkscape_command(svg, select=None, verbs=()):
+    """
+    Executes a list of commands, a mixture of verbs, selects etc.
+
+    inkscape_command('<svg...>', ('verb', 'VerbName'), ...)
+    """
+    with TemporaryDirectory(prefix="inkscape-command") as tmpdir:
+        svg_file = write_svg(svg, tmpdir, "input.svg")
+        select = ("select", select) if select else None
+        verbs += ("FileSave", "FileQuit")
+        inkscape(svg_file, select, batch_process=True, verb=";".join(verbs))
+        with open(svg_file, "rb") as fhl:
+            return fhl.read()
+
+
+def take_snapshot(svg, dirname, name="snapshot", ext="png", dpi=96, **kwargs):
+    """
+    Take a snapshot of the given svg file.
+
+    Resulting filename is yielded back, after generator finishes, the
+    file is deleted so you must deal with the file inside the for loop.
+    """
+    svg_file = write_svg(svg, dirname, name + ".svg")
+    ext_file = os.path.join(dirname, name + "." + str(ext).lower())
+    inkscape(
+        svg_file, export_dpi=dpi, export_filename=ext_file, export_type=ext, **kwargs
+    )
+    return ext_file
+
+
+def is_inkscape_available():
+    """Return true if the Inkscape executable is available."""
+    try:
+        return bool(which(INKSCAPE_EXECUTABLE_NAME))
+    except CommandNotFound:
+        return False