def test_NoParamsForUSER(self):
        """
        Issuing USER without a username is a syntax error.
        """
        return self.assertCommandFailed(
            'USER',
            ['500 Syntax error: USER requires an argument.'])

        Issuing USER without a username is a syntax error.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_ftp.py