def setUp(self):
        """
        Create a pb server using L{Echoer} protocol and connect a client to it.
        """
        self.serverFactory = pb.PBServerFactory(Echoer())
        clientFactory = pb.PBClientFactory()
        client, self.server, self.pump = connectServerAndClient(
            test=self,
            clientFactory=clientFactory,
            serverFactory=self.serverFactory)
        self.ref = self.successResultOf(clientFactory.getRootObject())

        Create a pb server using L{Echoer} protocol and connect a client to it.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/spread/test/test_pb.py