code: def send_heart_beat_msg(self):
          '''定时发送GET_PARAMETER消息保活'''
          if self.running:
              self.do_get_parameter()
              threading.Timer(HEARTBEAT_INTERVAL, self.send_heart_beat_msg).start(f send_heart_beat_msg(self):
          '''定时发送GET_PARAMETER消息保活'''
          if self.running:
              self.do_get_parameter()
              threading.Timer(HEARTBEAT_INTERVAL, self.send_heart_beat_msg).start()
docs: 定时发送GET_PARAMETER消息保活