code: func NewRateLimitedTimedQueue(limiter flowcontrol.RateLimiter) *RateLimitedTimedQueue {
  	return &RateLimitedTimedQueue{
  		queue: UniqueQueue{
  			queue: TimedQueue{},
  			set:   sets.NewString(),
  		},
  		limiter: limiter,
  	}
  }
docs: // NewRateLimitedTimedQueue creates new queue which will use given
  // RateLimiter to oversee execution.