Since PR #3067 I am unable to build from source (under windows).

This PR added a get_extension method to class FreeType in setupext.py.
A easy workaround is to explicitly return the default None under windows platform, but this seems a bit dirty.

def get_extension(self):
    ext = make_extension('freetype2', [])
    self.add_flags(ext)
    if sys.platform == 'win32':
        return None
    else:
        return ext

I would be happy to submit a PR for this but I would like first to take the advice of a setup.py / windows expert...