Vibe codingHardvc-g501

Subject Ai code reviewLevel Mid–Senior~17 minCommon in Algorithms & data structures interviewsIndustries Software development

Question

An AI wrote this Django REST Framework serializer + view for a blog feed showing each post's author and tag list. The list endpoint is slow and the query count grows linearly with page size. Find the cause and fix it without changing the JSON shape.

python

1class PostSerializer(serializers.ModelSerializer):2    author_name = serializers.SerializerMethodField()3    tags = serializers.SerializerMethodField()4    class Meta:5        model = Post6        fields = ["id", "title", "author_name", "tags"]7    def get_author_name(self, obj):8        return obj.author.full_name        # FK9    def get_tags(self, obj):10        return [t.name for t in obj.tags.all()]  # M2M11 12class PostList(generics.ListAPIView):13    queryset = Post.objects.all()14    serializer_class = PostSerializer

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