old_contents: from rest_framework.routers import DefaultRouter
  from rest_framework_extensions.routers import NestedRouterMixin
  
  
  class DefaultRouterWithNesting(NestedRouterMixin, DefaultRouter):
      pass
  
new_contents: from rest_framework.routers import DefaultRouter, APIRootView
  from rest_framework_extensions.routers import NestedRouterMixin
  
  
  class DocsAPIRootView(APIRootView):
  
      # Overridden only to add documentation for BrowsableAPIRenderer.
  
      """
      Read the Docs APIv3 root endpoint.
  
      Full documentation at [https://docs.readthedocs.io/en/latest/api/v3.html](https://docs.readthedocs.io/en/latest/api/v3.html).
      """
  
      def get_view_name(self):
          return 'Read the Docs APIv3'
  
  
  class DefaultRouterWithNesting(NestedRouterMixin, DefaultRouter):
      APIRootView = DocsAPIRootView
      root_view_name = 'api-v3-root'
  
subject: Add documentation to the root view of BrowsableAPI