  
  
  @python_2_unicode_compatible
  class Poem(models.Model):
      poet = models.ForeignKey(Poet)
      name = models.CharField(max_length=100)
  
      def __str__(self):
          return self.name
  
 
</s>
    poet = models.ForeignKey(Poet, models.CASCADE)
  
  
  @python_2_unicode_compatible
  class Poem(models.Model):
    poet = models.ForeignKey(Poet, models.CASCADE)
      name = models.CharField(max_length=100)
  
      def __str__(self):
          return self.name
  
keep keep keep keep replace keep keep keep keep keep
 Fixed #21127 -- Started deprecation toward requiring on_delete for ForeignKey/OneToOneField
tests/model_formsets/models.py