code: func (ttles *TTLExpirationScheduler) AddBlob(blobRef reference.Canonical, ttl time.Duration) error {
  	ttles.Lock()
  	defer ttles.Unlock()
  
  	if ttles.stopped {
  		return fmt.Errorf("scheduler not started")
  	}
  
  	ttles.add(blobRef, ttl, entryTypeBlob)
  	return nil
  }
docs: // AddBlob schedules a blob cleanup after ttl expires