serializers.JSONField(required=True) might have validation issue for invalid JSON data

[Karunamay-murmu]

I have this model serializer for create a new post.

class PostCreateSerializer(serializers.ModelSerializer):
    body = serializers.JSONField(required=True)

    class Meta:
        model = Post
        fields = ['title', 'category', 'tags', 'body',
                  'meta_title', 'meta_description', ]

As the body is JSONField it should validate if the body field holds a valid JSON right?
Here is the view:

class PostCreateApiView(CreateAPIView):
    queryset = Post.objects.all()
    serializer_class = PostCreateSerializer
    permission_classes = [permissions.IsAuthenticated]

    def post(self, request, *args, **kwargs):
        user = request.user.userId
        serializer = PostCreateSerializer(
            data=request.data, context={'user_id': user})
        print(serializer.initial_data) # {"title": "title", "category": "1", "body": "{dawdad}"}
        print(serializer.is_valid()) # This returns true
        serializer.is_valid(raise_exception=True)
        # ----

The serializer.is_valid() is return True, while the serializer.initial_data['body'] data is a invalid JSON.
If that is a expected behavior than how can I validate for a valid JSON in body?