code: def send_key(self, key):
          
          _LOGGER.info('Queueing key %s', key)
          frame = self._get_key_event_frame(key)
  
          # Queue it to send immediately following the reception
          # of a keep-alive packet in an attempt to avoid bus collisions.
          self._send_queue.put({'frame': frame})
docs: Sends a key.