old_contents: # -*- coding: utf-8 -*-
  
  from rest_framework import serializers
  from .models import Note, NoteBook
  
  
  class NoteBookSerializer(serializers.ModelSerializer):
      class Meta:
          model = NoteBook
  
  
  class NoteSerializer(serializers.ModelSerializer):
      class Meta:
          model = Note
  
new_contents: # -*- coding: utf-8 -*-
  
  from rest_framework import serializers
  from .models import Note, NoteBook, NoteRevision
  
  
  class NoteBookSerializer(serializers.ModelSerializer):
      class Meta:
          model = NoteBook
  
  
  class NoteSerializer(serializers.ModelSerializer):
      class Meta:
          model = Note
  
  
  class NoteRevisionSerializer(serializers.ModelSerializer):
      class Meta:
          model = NoteRevision
  
subject: update serializer.py