code: func (b *Bundle) LanguageTranslationIDs(languageTag string) []string {
  	var ids []string
  	b.RLock()
  	for id := range b.translations[languageTag] {
  		ids = append(ids, id)
  	}
  	b.RUnlock()
  	return ids
  }
docs: // LanguageTranslationIDs returns the ids of all translations that have been added for a given language.