code: def install_builtin (translator, do_unicode):
      
      try:
          import __builtin__ as builtins
      except ImportError:
          # Python 3
          import builtins
      # Python 3 has no ugettext
      has_unicode = hasattr(translator, 'ugettext')
      if do_unicode and has_unicode:
          builtins.__dict__['_'] = translator.ugettext
          # also install ngettext
          builtins.__dict__['_n'] = translator.ungettext
      else:
          builtins.__dict__['_'] = translator.gettext
          # also install ngettext
          builtins.__dict__['_n'] = translator.ngettext
docs: Install _() and _n() gettext methods into default namespace.