code: def get_all_language_codes():
      
      languages = get_language_codes()
      if hasattr(settings, 'MSGID_LANGUAGE'):
          if not settings.MSGID_LANGUAGE in languages:
              languages.insert(0, settings.MSGID_LANGUAGE)
              
      return languages
docs: Returns all language codes defined in settings.LANGUAGES and also the
      settings.MSGID_LANGUAGE if defined.
      
      >>> from django.conf import settings
      >>> settings.MSGID_LANGUAGE = 'en-us'
      >>> settings.LANGUAGES = (('en','English'),('de','German'),('nl-be','Belgium dutch'),('fr-be','Belgium french'),)
      >>> sorted( get_language_codes() )
      ['en-us', 'en','de', 'nl-be','fr-be']
      
      :rtype: A :class:`list` of language codes.