code: func (s *ticketStore) ticketsInWindow(topic Topic) []ticketRef {
  	// Sanity check that the topic still exists before operating on it
  	if s.tickets[topic] == nil {
  		log.Warn("Listing non-existing discovery tickets", "topic", topic)
  		return nil
  	}
  	// Gather all the tickers in the next time window
  	var tickets []ticketRef
  
  	buckets := s.tickets[topic].buckets
  	for idx := timeBucket(0); idx < timeWindow; idx++ {
  		tickets = append(tickets, buckets[s.lastBucketFetched+idx]...)
  	}
  	log.Trace("Retrieved discovery registration tickets", "topic", topic, "from", s.lastBucketFetched, "tickets", len(tickets))
  	return tickets
  }
docs: // ticketsInWindow returns the tickets of a given topic in the registration window.