code: def at(self, cmd, *args, **kwargs):
          
          with self.lock:
              self.com_watchdog_timer.cancel()
              cmd(self.host, self.sequence, *args, **kwargs)
              self.sequence += 1
              self.com_watchdog_timer = threading.Timer(self.timer, self.commwdg)
              self.com_watchdog_timer.start()
docs: Wrapper for the low level at commands.
  
          This method takes care that the sequence number is increased after each
          at command and the watchdog timer is started to make sure the drone
          receives a command at least every second.