code: def handle(self, targetdir, app=None, **options):
          
          translation.activate(settings.LANGUAGE_CODE)
          if app:
              unpack = app.split('.')
  
              if len(unpack) == 2:
                  models = [get_model(unpack[0], unpack[1])]
              elif len(unpack) == 1:
                  models = get_models(get_app(unpack[0]))
          else:
              models = get_models()
          
          messagemaker = MakeModelMessages(targetdir)
          
          for model in models:
              if hasattr(model, 'localized_fields'):
                  for instance in model.objects.all():
                      messagemaker(instance)
docs: command execution