code: def serve():
      
      logging.getLogger().setLevel(logging.DEBUG)
      logging.info('Python Tornado Crossdock Server Running ...')
      server = Server(DefaultServerPortTChannel)
      endtoend_handler = EndToEndHandler()
      app = make_app(server, endtoend_handler)
      app.listen(DefaultClientPortHTTP)
      app.listen(DefaultServerPortHTTP)
      server.tchannel.listen()
      tornado.ioloop.IOLoop.current().start()
docs: main entry point