def test_tcpNoDelay(self):
        """
        The transport of a protocol connected with L{IReactorTCP.connectTCP} or
        L{IReactor.TCP.listenTCP} can have its I{TCP_NODELAY} state inspected
        and manipulated with L{ITCPTransport.getTcpNoDelay} and
        L{ITCPTransport.setTcpNoDelay}.
        """
        def check(serverProtocol, clientProtocol):
            for p in [serverProtocol, clientProtocol]:
                transport = p.transport
                self.assertEqual(transport.getTcpNoDelay(), 0)
                transport.setTcpNoDelay(1)
                self.assertEqual(transport.getTcpNoDelay(), 1)
                transport.setTcpNoDelay(0)
                self.assertEqual(transport.getTcpNoDelay(), 0)
        return self._connectedClientAndServerTest(check)

        The transport of a protocol connected with L{IReactorTCP.connectTCP} or
        L{IReactor.TCP.listenTCP} can have its I{TCP_NODELAY} state inspected
        and manipulated with L{ITCPTransport.getTcpNoDelay} and
        L{ITCPTransport.setTcpNoDelay}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_tcp.py