fix url

cartero/admin.py

 # -*- coding: utf-8 -*-
 from django.contrib import admin
+from django.conf.urls import url
 from django.db.models import Count
 from django.utils.translation import ugettext_lazy as _
 
@@ -95,11 +96,10 @@ class EmailTemplateAdmin(admin.ModelAdmin):
     def get_urls(self):
         urls = super(EmailTemplateAdmin, self).get_urls()
         my_urls = [
-            '',
-            (r'^add/$',
-             self.admin_site.admin_view(CreateTemplateView.as_view())),
-            (r'^(?P<pk>\d+)/change/$',
-             self.admin_site.admin_view(UpdateTemplateView.as_view()))
+            url(r'^add/$',
+                self.admin_site.admin_view(CreateTemplateView.as_view())),
+            url(r'^(?P<pk>\d+)/change/$',
+                self.admin_site.admin_view(UpdateTemplateView.as_view()))
         ]
         return my_urls + urls