def test_extraKeywords(self):
        """
        When passed a keyword parameter other than C{extraCertificateOptions},
        L{sslverify.optionsForClientTLS} raises an exception just like a
        normal Python function would.
        """
        error = self.assertRaises(
            TypeError,
            sslverify.optionsForClientTLS,
            hostname=u'alpha', someRandomThing=u'beta',
        )
        self.assertEqual(
            str(error),
            "optionsForClientTLS() got an unexpected keyword argument "
            "'someRandomThing'"
        )

        When passed a keyword parameter other than C{extraCertificateOptions},
        L{sslverify.optionsForClientTLS} raises an exception just like a
        normal Python function would.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_sslverify.py