def test_chat(self):
        """
        Test that I{get} and I{put} commands are responded to correctly by
        L{postfix.PostfixTCPMapServer} when its factory is an instance of
        L{postifx.PostfixTCPMapDictServerFactory}.
        """
        factory = postfix.PostfixTCPMapDictServerFactory(self.data)
        transport = StringTransport()

        protocol = postfix.PostfixTCPMapServer()
        protocol.service = factory
        protocol.factory = factory
        protocol.makeConnection(transport)

        for input, expected_output in self.chat:
            protocol.lineReceived(input)
            self.assertEqual(
                transport.value(), expected_output,
                'For %r, expected %r but got %r' % (
                    input, expected_output, transport.value()))
            transport.clear()
        protocol.setTimeout(None)

        Test that I{get} and I{put} commands are responded to correctly by
        L{postfix.PostfixTCPMapServer} when its factory is an instance of
        L{postifx.PostfixTCPMapDictServerFactory}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_postfix.py