def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def test_invalid_field_types(self):
        class POINT(Structure):
            pass
        self.assertRaises(TypeError, setattr, POINT, "_fields_", [("x", 1), ("y", 2)])