def test_multipleClasses(self):
        """
        Test that multiple instances have distinct states.
        """
        proto = self.proto
        proto.dataReceived(self.transport.value())
        proto.currentEncryptions = MockCipher()
        proto.outgoingCompression = MockCompression()
        proto.incomingCompression = MockCompression()
        proto.setService(MockService())
        proto2 = MockTransportBase()
        proto2.makeConnection(proto_helpers.StringTransport())
        proto2.sendIgnore(b'')
        self.assertNotEqual(proto.gotVersion, proto2.gotVersion)
        self.assertNotEqual(proto.transport, proto2.transport)
        self.assertNotEqual(proto.outgoingPacketSequence,
                            proto2.outgoingPacketSequence)
        self.assertNotEqual(proto.incomingPacketSequence,
                            proto2.incomingPacketSequence)
        self.assertNotEqual(proto.currentEncryptions,
                            proto2.currentEncryptions)
        self.assertNotEqual(proto.service, proto2.service)

        Test that multiple instances have distinct states.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_transport.py