code: def from_xxx(cls, xxx):
          
          xxx = str(xxx).lower()
          if xxx is 'unknown':
              return UnknownLanguage(xxx)
          try:
              return cls._from_xyz('LanguageID', xxx)
          except NotALanguageException:
              log.warning('Unknown LanguageId: {}'.format(xxx))
              return UnknownLanguage(xxx)
docs: Create a new Language instance from a LanguageID string
          :param xxx: LanguageID as string
          :return: Language instance with instance.xxx() == xxx if xxx is valid else instance of UnknownLanguage