  
  
  class ParkingLot4(models.Model):
      # Test parent_link connector can be discovered in abstract classes.
      parent = models.OneToOneField(Place, parent_link=True)
  
      class Meta:
          abstract = True
  
  
 
</s> remove     parent = models.OneToOneField(Place, parent_link=True)
 </s> add     parent = models.OneToOneField(Place, models.CASCADE, parent_link=True) </s> remove     parent = models.OneToOneField(Place)
 </s> add     parent = models.OneToOneField(Place, models.CASCADE) </s> remove     post = models.ForeignKey(Post, related_name='attached_%(class)s_set')
 </s> add     post = models.ForeignKey(Post, models.CASCADE, related_name='attached_%(class)s_set') </s> remove     title = models.ForeignKey(Title, related_name='attached_%(app_label)s_%(class)s_set')
 </s> add     title = models.ForeignKey(Title, models.CASCADE, related_name='attached_%(app_label)s_%(class)s_set') </s> remove     vehicle = models.OneToOneField(Vehicle, parent_link=True, related_name='vehicle_%(app_label)s_%(class)s')
 </s> add     vehicle = models.OneToOneField(
        Vehicle,
        models.CASCADE,
        parent_link=True,
        related_name='vehicle_%(app_label)s_%(class)s',
    )
    parent = models.OneToOneField(Place, models.CASCADE, parent_link=True)
  
  
  class ParkingLot4(models.Model):
      # Test parent_link connector can be discovered in abstract classes.
    parent = models.OneToOneField(Place, models.CASCADE, parent_link=True)
  
      class Meta:
          abstract = True
  
  
keep keep keep keep replace keep keep keep keep keep
 Fixed #21127 -- Started deprecation toward requiring on_delete for ForeignKey/OneToOneField 
tests/model_inheritance_regress/models.py