code: def _handle_unsubscribed(self, *args, chanId=None, **kwargs):
          
          log.debug("_handle_unsubscribed: %s - %s", chanId, kwargs)
          try:
              self.channels.pop(chanId)
          except KeyError:
              raise NotRegisteredError()
  
          try:
              self._heartbeats.pop(chanId)
          except KeyError:
              pass
  
          try:
              self._late_heartbeats.pop(chanId)
          except KeyError:
              pass
docs: Handles responses to unsubscribe() commands - removes a channel id from
          the client.
          :param chanId: int, represent channel id as assigned by server