如何在Django rest框架中使用RelatedField？

from django.db import models

class Author(models.Model):
    name = models.CharField(max_length=100)

class Book(models.Model):
    title = models.CharField(max_length=100)
    author = models.ForeignKey(Author, on_delete=models.CASCADE)

from rest_framework import serializers
from .models import Author, Book

class BookSerializer(serializers.ModelSerializer):
    author = serializers.PrimaryKeyRelatedField(queryset=Author.objects.all())

    class Meta:
        model = Book
        fields = ['title', 'author']

from rest_framework import viewsets
from .models import Book
from .serializers import BookSerializer

class BookViewSet(viewsets.ModelViewSet):
    queryset = Book.objects.all()
    serializer_class = BookSerializer