With Django 1.5, an import causes a DeprecationWarning

I'm running django-tablib with [the Django 1.5 release candidate](https://www.djangoproject.com/weblog/2013/jan/04/15-rc-1/). It logs a deprecation warning from django-tablib. If I change warnings to errors and enable tracebacks, I see:

    File "django_tablib/admin.py", line 30, in get_urls
      from django.conf.urls.defaults import patterns, url
    File "django/conf/urls/defaults.py", line 3, in <module>
      DeprecationWarning)
    
    DeprecationWarning: django.conf.urls.defaults is deprecated; use django.conf.urls instead