Most Python files should include the following boilerplate at the top of the file, right after the
comment header and
from __future__ import:
__metaclass__ = type
Python 2 has “new-style classes” and “old-style classes” whereas Python 3 only has new-style classes.
__metaclass__ = type boilerplate makes every class defined in that file into
a new-style class as well.
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