          ordering = ['id']
  
  
  class BookReview(models.Model):
      book = models.ForeignKey(BookWithYear)
      notes = models.TextField(null=True, blank=True)
  
  
  # Models for default manager tests
  
 
</s> remove     parent = models.ForeignKey('self', null=True, blank=True)
 </s> add     parent = models.ForeignKey('self', models.SET_NULL, null=True, blank=True) </s> remove     book = models.OneToOneField(Book, parent_link=True)
 </s> add     book = models.OneToOneField(Book, models.CASCADE, parent_link=True) </s> remove     fashionista = models.ForeignKey(Fashionista)
    item = models.ForeignKey(OutfitItem)
 </s> add     fashionista = models.ForeignKey(Fashionista, models.CASCADE)
    item = models.ForeignKey(OutfitItem, models.CASCADE) </s> remove     capo_famiglia = models.ForeignKey(CapoFamiglia)
 </s> add     capo_famiglia = models.ForeignKey(CapoFamiglia, models.CASCADE) </s> remove     et = models.ForeignKey(ExtraTerrestrial)
 </s> add     et = models.ForeignKey(ExtraTerrestrial, models.CASCADE)
    book = models.ForeignKey(BookWithYear, models.CASCADE)
          ordering = ['id']
  
  
  class BookReview(models.Model):
    book = models.ForeignKey(BookWithYear, models.CASCADE)
      notes = models.TextField(null=True, blank=True)
  
  
  # Models for default manager tests
  
keep keep keep keep replace keep keep keep keep keep
 Fixed #21127 -- Started deprecation toward requiring on_delete for ForeignKey/OneToOneField 
tests/prefetch_related/models.py