Use key_name instead of link_id
Some entities do not have a link_id, but all entities are guaranteed
to have a key_name (or an id).
from django.conf.urls.defaults import *
urlpatterns = patterns('',
# test_client modeltest urls
(r'^test_client/', include('modeltests.test_client.urls')),
# Always provide the auth system login and logout views
(r'^accounts/login/$', 'django.contrib.auth.views.login', {'template_name': 'login.html'}),
(r'^accounts/logout/$', 'django.contrib.auth.views.logout'),
# test urlconf for {% url %} template tag
(r'^url_tag/', include('regressiontests.templates.urls')),
)