def METHOD_NAME(self):
    ns = Namespace(
        role="fake-role",
        scope=None,
        system_assigned=None,
        user_assigned=None)
    with self.assertRaises(InvalidArgumentValueError) as context:
        validate_app_identity_assign_or_warning(ns)
    self.assertTrue("Parameter \"role\" and \"scope\" should be used together." in str(context.exception))