old_contents: from dwitter.models import Comment, Dweet
  from django.shortcuts import render
  from dwitter.models import Comment
  from dwitter.permissions import IsAuthorOrReadOnly
  from dwitter.serializers import CommentSerializer, DweetSerializer
  from dwitter.serializers import UserSerializer
  from django.utils import timezone
  from django.contrib.auth.models import User
  from django_filters import FilterSet, NumberFilter, CharFilter
  from rest_framework import viewsets, mixins, permissions
  from rest_framework.pagination import LimitOffsetPagination
  
  
  class CommentViewSet(viewsets.ModelViewSet):
      pagination_class = LimitOffsetPagination
      default_limit = 10
      queryset = Comment.objects.all()
      queryset = queryset.select_related('author').prefetch_related('reply_to')
      serializer_class = CommentSerializer
      filter_fields = ('reply_to', 'author')
      permission_classes = (permissions.IsAuthenticatedOrReadOnly,
                            IsAuthorOrReadOnly, )
  
      def perform_create(self, serializer):
          serializer.save(author=self.request.user, posted=timezone.now())
  
  
  class DweetFilterSet(FilterSet):
      remix_of = NumberFilter(name='reply_to')
      author = CharFilter(name='author__username')
  
      class Meta:
          model = Dweet
          fields = ['remix_of', 'author']
  
  
  class DweetViewSet(mixins.RetrieveModelMixin,
                     mixins.ListModelMixin,
                     viewsets.GenericViewSet):
      queryset = Dweet.objects.all()
      queryset = queryset.select_related('author')
      queryset = queryset.prefetch_related('likes')
      filter_class = DweetFilterSet
      serializer_class = DweetSerializer
  
  
  class UserViewSet(mixins.RetrieveModelMixin,
                    viewsets.GenericViewSet):
      queryset = User.objects.all()
      serializer_class = UserSerializer
      lookup_field = 'username'
  
  
  def about(request):
      return render(request, 'about.html')
  
new_contents: from dwitter.models import Comment, Dweet
  from django.shortcuts import render
  from dwitter.permissions import IsAuthorOrReadOnly
  from dwitter.serializers import CommentSerializer, DweetSerializer
  from dwitter.serializers import UserSerializer
  from django.utils import timezone
  from django.contrib.auth.models import User
  from django_filters import FilterSet, NumberFilter, CharFilter
  from rest_framework import viewsets, mixins, permissions
  from rest_framework.pagination import LimitOffsetPagination
  
  
  class CommentViewSet(viewsets.ModelViewSet):
      pagination_class = LimitOffsetPagination
      default_limit = 10
      queryset = Comment.objects.all()
      queryset = queryset.select_related('author').prefetch_related('reply_to')
      serializer_class = CommentSerializer
      filter_fields = ('reply_to', 'author')
      permission_classes = (permissions.IsAuthenticatedOrReadOnly,
                            IsAuthorOrReadOnly, )
  
      def perform_create(self, serializer):
          serializer.save(author=self.request.user, posted=timezone.now())
  
  
  class DweetFilterSet(FilterSet):
      remix_of = NumberFilter(name='reply_to')
      author = CharFilter(name='author__username')
  
      class Meta:
          model = Dweet
          fields = ['remix_of', 'author']
  
  
  class DweetViewSet(mixins.RetrieveModelMixin,
                     mixins.ListModelMixin,
                     viewsets.GenericViewSet):
      queryset = Dweet.objects.all()
      queryset = queryset.select_related('author')
      queryset = queryset.prefetch_related('likes')
      filter_class = DweetFilterSet
      serializer_class = DweetSerializer
  
  
  class UserViewSet(mixins.RetrieveModelMixin,
                    viewsets.GenericViewSet):
      queryset = User.objects.all()
      serializer_class = UserSerializer
      lookup_field = 'username'
  
  
  def about(request):
      return render(request, 'about.html')
  
subject: Fix lint error