new_contents: from core.models.user import AtmosphereUser
  from rest_framework import serializers
  
  
  class UserSerializer(serializers.ModelSerializer):
      class Meta:
          model = AtmosphereUser
          fields = ('id', 'username', 'first_name', 'last_name', 'email', 'is_staff', 'is_superuser')
  
subject: add user serializer