def test_win32Definition(self):
        """
        When building on Windows NT, the WIN32 macro will be defined as 1 on
        the extensions.
        """
        ext = ConditionalExtension("whatever", ["whatever.c"],
                                   define_macros=[("whatever", 2)])

        args = getSetupArgs(extensions=[ext], readme=None)

        builder = args["cmdclass"]["build_ext"](Distribution())
        self.patch(os, "name", "nt")
        builder.prepare_extensions()
        self.assertEqual(ext.define_macros, [("whatever", 2), ("WIN32", 1)])

        When building on Windows NT, the WIN32 macro will be defined as 1 on
        the extensions.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/test/test_setup.py