def test_interface(self):
        """
        The C{connect} method returns an object providing L{IConnector}.
        """
        reactor = self.buildReactor()
        connector = self.connect(reactor, ClientFactory())
        self.assertTrue(verifyObject(IConnector, connector))

        The C{connect} method returns an object providing L{IConnector}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/connectionmixins.py