def post(self, request):
    user = request.user
    serializer = DeleteFollowSerializer(data=request.data)
    serializer.is_valid(raise_exception=True)
    data = serializer.validated_data
    user_to_unfollow_username = data.get('username')
    User = get_user_model()
    user_to_unfollow = User.objects.get(username=user_to_unfollow_username)
    with transaction.atomic():
        user.unfollow_user_with_id(user_to_unfollow.pk)
    response_serializer = FollowUserSerializer(user_to_unfollow, context={'request': request})
    return Response(response_serializer.data, status=status.HTTP_200_OK)
def post(self, request):
    user = request.user
    serializer = DeleteFollowSerializer(data=request.data)
    serializer.is_valid(raise_exception=True)
    data = serializer.validated_data
    user_to_unfollow_username = data.get('username')
    User = get_user_model()
    user_to_unfollow = User.objects.get(username=user_to_unfollow_username)
    with transaction.atomic():
        user.unfollow_user_with_id(user_to_unfollow.pk)
    response_serializer = FollowUserSerializer(user_to_unfollow, context={'request': request})
    return Response(response_serializer.data, status=status.HTTP_200_OK)