code: def filter_wait_on_queues(max_waiting):
      
      def filter_func(log_line):
          waiting = int(max_waiting)
          return waiting >= log_line.time_wait_queues
  
      return filter_func
docs: Filter :class:`.Line` objects by their queueing time in
      HAProxy.
  
      :param max_waiting: maximum time, in milliseconds, a request is waiting on
        HAProxy prior to be delivered to a backend server. If HAProxy takes less
        than that time the log line is counted.
      :type max_waiting: string
      :returns: a function that filters by HAProxy queueing time.
      :rtype: function