code: def process_streamer(self, streamer, callback=None):
          
  
          index = streamer.index
  
          if index in self._in_progress_streamers:
              raise InternalError("You cannot add a streamer again until it has finished streaming.")
  
          queue_item = QueuedStreamer(streamer, callback)
          self._in_progress_streamers.add(index)
  
          self._logger.debug("Streamer %d: queued to send %d readings", index, queue_item.initial_count)
          self._queue.put_nowait(queue_item)
docs: Start streaming a streamer.
  
          Args:
              streamer (DataStreamer): The streamer itself.
              callback (callable): An optional callable that will be called as:
                  callable(index, success, highest_id_received_from_other_side)