      pages = models.IntegerField()
      rating = models.FloatField()
      price = models.DecimalField(decimal_places=2, max_digits=6)
      authors = models.ManyToManyField(Author)
      contact = models.ForeignKey(Author, related_name='book_contact_set')
      publisher = models.ForeignKey(Publisher)
      pubdate = models.DateField()
  
      def __str__(self):
          return self.name
  
 
</s>
    contact = models.ForeignKey(Author, models.CASCADE, related_name='book_contact_set')
    publisher = models.ForeignKey(Publisher, models.CASCADE)
      pages = models.IntegerField()
      rating = models.FloatField()
      price = models.DecimalField(decimal_places=2, max_digits=6)
      authors = models.ManyToManyField(Author)
    contact = models.ForeignKey(Author, models.CASCADE, related_name='book_contact_set')
    publisher = models.ForeignKey(Publisher, models.CASCADE)
    contact = models.ForeignKey(Author, models.CASCADE, related_name='book_contact_set')
    publisher = models.ForeignKey(Publisher, models.CASCADE)
      pubdate = models.DateField()
  
      def __str__(self):
          return self.name
  
keep keep keep keep replace replace keep keep keep keep keep
 Fixed #21127 -- Started deprecation toward requiring on_delete for ForeignKey/OneToOneField
tests/annotations/models.py