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+metaclass-boilerplate
+=====================
+
+Most Python files should include the following boilerplate at the top of the file, right after the
+comment header and ``from __future__ import``:
+
+.. code-block:: python
+
+    __metaclass__ = type
+
+
+Python 2 has "new-style classes" and "old-style classes" whereas Python 3 only has new-style classes.
+Adding the ``__metaclass__ = type`` boilerplate makes every class defined in that file into
+a new-style class as well.
+
+.. code-block:: python
+
+    from __future__ import absolute_import, division, print_function
+    __metaclass__ = type
+
+    class Foo:
+        # This is a new-style class even on Python 2 because of the __metaclass__
+        pass