              msg = _('The %(name)s "%(obj)s" was added successfully. You may edit it again below.') % msg_dict
              self.message_user(request, msg)
              if post_url_continue is None:
                  post_url_continue = reverse('admin:%s_%s_change' %
                                              (opts.app_label, opts.module_name),
                                              args=(pk_value,),
                                              current_app=self.admin_site.name)
              if "_popup" in request.POST:
                  post_url_continue += "?_popup=1"
              return HttpResponseRedirect(post_url_continue)
 
</s> remove                                         (opts.app_label, opts.module_name),
 </s> add                                         (opts.app_label, opts.model_name), </s> remove                                         (opts.app_label, opts.module_name),
 </s> add                                         (opts.app_label, opts.model_name), </s> remove                                (opts.app_label, opts.module_name),
 </s> add                                (opts.app_label, opts.model_name), </s> remove                                (opts.app_label, opts.module_name),
 </s> add                                (opts.app_label, opts.model_name), </s> remove                                     (opts.app_label, opts.module_name),
 </s> add                                     (opts.app_label, opts.model_name),
                                            (opts.app_label, opts.model_name),
              msg = _('The %(name)s "%(obj)s" was added successfully. You may edit it again below.') % msg_dict
              self.message_user(request, msg)
              if post_url_continue is None:
                  post_url_continue = reverse('admin:%s_%s_change' %
                                            (opts.app_label, opts.model_name),
                                              args=(pk_value,),
                                              current_app=self.admin_site.name)
              if "_popup" in request.POST:
                  post_url_continue += "?_popup=1"
              return HttpResponseRedirect(post_url_continue)
keep keep keep keep replace keep keep keep keep keep
 Fixed #19689 -- Renamed `Model._meta.module_name` to `model_name`. 
django/contrib/admin/options.py