from typing import Type from rest_framework import serializers from apps.geology.models import Category, Geology class CategorySerializer(serializers.ModelSerializer): count = serializers.SerializerMethodField() class Meta: model: Type[Category] = Category fields: str = ("id", "count", "name", "created_at", "updated_at") def get_count(self, obj): return Geology.objects.filter(category=obj).count()