code: def activate(lang=None):
      
      if lang is None:
          lang = locale.getlocale()[0]
      tr = gettext.translation("argparse", os.path.join(locpath, "locale"),
                               [lang], fallback=True)
      argparse._ = tr.gettext
      argparse.ngettext = tr.ngettext
docs: Activate a translation for lang.
  
  If lang is None, then the language of locale.getdefaultlocale() is used.
  If the translation file does not exist, the original messages will be used.