old_contents: from blog.sitemaps import (
      PostArchiveSitemap, PostSitemap)
  from organizer.sitemaps import (
      StartupSitemap, TagSitemap)
  
  sitemaps = {
      'post-archives': PostArchiveSitemap,
      'posts': PostSitemap,
      'startups': StartupSitemap,
      'tags': TagSitemap,
  }
  
new_contents: from django.contrib.sitemaps import Sitemap
  from django.core.urlresolvers import reverse
  
  from blog.sitemaps import (
      PostArchiveSitemap, PostSitemap)
  from organizer.sitemaps import (
      StartupSitemap, TagSitemap)
  
  
  class RootSitemap(Sitemap):
      priority = 0.6
  
      def items(self):
          return [
              'about_site',
              'blog_post_list',
              'contact',
              'dj_auth:login'
              'organizer_startup_list',
              'organizer_tag_list',
          ]
  
      def location(self, url_name):
          return reverse(url_name)
  
  
  sitemaps = {
      'post-archives': PostArchiveSitemap,
      'posts': PostSitemap,
      'roots': RootSitemap,
      'startups': StartupSitemap,
      'tags': TagSitemap,
  }
  
subject: Implement RootSitemap.