code: func (s *attrStore) Open() error {
  	// Open storage.
  	db, err := bolt.Open(s.path, 0666, &bolt.Options{Timeout: 1 * time.Second})
  	if err != nil {
  		return errors.Wrap(err, "opening storage")
  	}
  	s.db = db
  
  	// Initialize database.
  	if err := s.db.Update(func(tx *bolt.Tx) error {
  		_, err := tx.CreateBucketIfNotExists([]byte("attrs"))
  		return err
  	}); err != nil {
  		return errors.Wrap(err, "initializing")
  	}
  
  	return nil
  }
docs: // Open opens and initializes the store.