def test_reactorParametrizationInClient(self):
        """
        L{internet._AbstractClient} supports a C{reactor} keyword arguments
        that can be used to parametrize the reactor used to create new client
        connections.
        """
        reactor = MemoryReactor()

        factory = protocol.ClientFactory()
        t = internet.TCPClient('127.0.0.1', 1234, factory, reactor=reactor)
        t.startService()
        self.assertEqual(
            reactor.tcpClients.pop()[:3], ('127.0.0.1', 1234, factory))

        L{internet._AbstractClient} supports a C{reactor} keyword arguments
        that can be used to parametrize the reactor used to create new client
        connections.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_application.py