old_contents: from snippets.models import Snippet
  from snippets.serializers import SnippetSerializer
  from rest_framework import generics
  from rest_framework import permissions
  from django.contrib.auth.models import User
  from snippets.serializers import UserSerializer
  from snippets.permissions import IsOwnerOrReadOnly
  
  
  class UserList(generics.ListAPIView):
      queryset = User.objects.all()
      serializer_class = UserSerializer
  
  
  class UserDetail(generics.RetrieveAPIView):
      queryset = User.objects.all()
      serializer_class = UserSerializer
  
  
  class SnippetList(generics.ListCreateAPIView):
      queryset = Snippet.objects.all()
      serializer_class = SnippetSerializer
      permission_classes = (permissions.IsAuthenticatedOrReadOnly,)
  
      def perform_create(self, serializer):
          serializer.save(owner=self.request.user)
  
  
  class SnippetDetail(generics.RetrieveUpdateDestroyAPIView):
      queryset = Snippet.objects.all()
      serializer_class = SnippetSerializer
      permission_classes = (permissions.IsAuthenticatedOrReadOnly,
                            IsOwnerOrReadOnly)
  
new_contents: from snippets.models import Snippet
  from snippets.serializers import SnippetSerializer
  from rest_framework import generics
  from rest_framework import permissions
  from django.contrib.auth.models import User
  from snippets.serializers import UserSerializer
  from snippets.permissions import IsOwnerOrReadOnly
  from rest_framework.decorators import api_view
  from rest_framework.response import Response
  from rest_framework.reverse import reverse
  
  
  @api_view(("GET", ))
  def api_root(request, format=None):
      return Response({
          "users": reverse("user-list", request=request, format=format),
          "snippets": reverse("snippet-list", request=request, format=format)
      })
  
  
  
  class UserList(generics.ListAPIView):
      queryset = User.objects.all()
      serializer_class = UserSerializer
  
  
  class UserDetail(generics.RetrieveAPIView):
      queryset = User.objects.all()
      serializer_class = UserSerializer
  
  
  class SnippetList(generics.ListCreateAPIView):
      queryset = Snippet.objects.all()
      serializer_class = SnippetSerializer
      permission_classes = (permissions.IsAuthenticatedOrReadOnly,)
  
      def perform_create(self, serializer):
          serializer.save(owner=self.request.user)
  
  
  class SnippetDetail(generics.RetrieveUpdateDestroyAPIView):
      queryset = Snippet.objects.all()
      serializer_class = SnippetSerializer
      permission_classes = (permissions.IsAuthenticatedOrReadOnly,
                            IsOwnerOrReadOnly)
  
subject: Add an api view for the API root