old_contents: from django.contrib.sitemaps.views import sitemap
  from django.conf.urls import url, include
  from django.contrib import admin
  
  urlpatterns = [
      url(r'^', include('blog.urls')),
      url(r'^blog', include('blog.urls')),
      url(r'^admin/', admin.site.urls),
  
      url(r'^sitemap\.xml$', sitemap, {'sitemaps': sitemaps}, name='django.contrib.sitemaps.views.sitemap')
  ]
  
new_contents: from django.contrib.sitemaps.views import sitemap
  from django.conf.urls import url, include
  from django.contrib import admin
  from django.views.generic import RedirectView
  
  
  urlpatterns = [
      url(r'^$', RedirectView.as_view(url='blog/', permanent=False)),
      url(r'^blog/', include('blog.urls')),
      url(r'^admin/', admin.site.urls),
      #url(r'^sitemap\.xml$', sitemap, {'sitemaps': sitemaps}, name='django.contrib.sitemaps.views.sitemap')
  ]
  
subject: add url patterns for categories subapp