def test_connectProtocolReturnsConnectResult(self):
        """
        C{endpoints.connectProtocol} returns the result of calling the given
        endpoint's C{connect()} method.
        """
        result = defer.Deferred()
        class Endpoint:
            def connect(self, factory):
                """
                Return a marker object for use in our assertion.
                """
                return result

        endpoint = Endpoint()
        self.assertIs(result, endpoints.connectProtocol(endpoint, object()))

        C{endpoints.connectProtocol} returns the result of calling the given
        endpoint's C{connect()} method.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/test_endpoints.py