old_contents: from django.conf.urls import patterns, include, url
  from django.contrib import admin
  
  import matmat.views
  
  admin.autodiscover()
  
  urlpatterns = patterns(
      '',
      url(r'^user/', include('proso_user.urls')),
      url(r'^models/', include('proso_models.urls')),
      url(r'^common/', include('proso_common.urls')),
      url(r'^concepts/', include('proso_concepts.urls', namespace="concepts")),
      url(r'^feedback/', include('proso_feedback.urls')),
      url(r'^tasks/', include('proso_tasks.urls', namespace="tasks")),
      url(r'^admin/', include(admin.site.urls)),
      url(r'^admin/', include(admin.site.urls)),
      url(r'^', include('social.apps.django_app.urls', namespace='social')),
      url(r'^small_concepts/(?P<skill_identifier>\w+)$', matmat.views.small_concepts, name='small_concepts'),
      url(r'^.*$', matmat.views.index, name='index'),
  )
new_contents: from django.conf.urls import patterns, include, url
  from django.contrib import admin
  
  import matmat.views
  
  admin.autodiscover()
  
  urlpatterns = [
      url(r'^user/', include('proso_user.urls')),
      url(r'^models/', include('proso_models.urls')),
      url(r'^common/', include('proso_common.urls')),
      url(r'^concepts/', include('proso_concepts.urls', namespace="concepts")),
      url(r'^feedback/', include('proso_feedback.urls')),
      url(r'^tasks/', include('proso_tasks.urls', namespace="tasks")),
      url(r'^admin/', include(admin.site.urls)),
      url(r'^admin/', include(admin.site.urls)),
      url(r'^', include('social.apps.django_app.urls', namespace='social')),
      url(r'^small_concepts/(?P<skill_identifier>\w+)$', matmat.views.small_concepts, name='small_concepts'),
      url(r'^.*$', matmat.views.index, name='index'),
  ]
  
subject: use new url format