code: def start_transport(self):
          
          if self.transport:
              if self.transport.connect():
                  self.log.debug("Service successfully connected to transport layer")
              else:
                  raise RuntimeError("Service could not connect to transport layer")
              # direct all transport callbacks into the main queue
              self._transport_interceptor_counter = itertools.count()
              self.transport.subscription_callback_set_intercept(
                  self._transport_interceptor
              )
          else:
              self.log.debug("No transport layer defined for service. Skipping.")
docs: If a transport object has been defined then connect it now.