code: def handleAllSync(self, deq: deque, limit=None) -> int:
          
          count = 0
          while deq and (not limit or count < limit):
              count += 1
              msg = deq.popleft()
              self.handleSync(msg)
          return count
docs: Synchronously handle all items in a deque.
  
          :param deq: a deque of items to be handled by this router
          :param limit: the number of items in the deque to the handled
          :return: the number of items handled successfully