      system_info = models.ForeignKey(SystemInfo, models.CASCADE)
      forum_name = models.CharField(max_length=32)
  
  
  @python_2_unicode_compatible
  class Post(models.Model):
      forum = models.ForeignKey(Forum, models.SET_NULL, null=True)
      title = models.CharField(max_length=32)
  
      def __str__(self):
 
</s>
      system_info = models.ForeignKey(SystemInfo, models.CASCADE)
      forum_name = models.CharField(max_length=32)
  
  

  class Post(models.Model):
      forum = models.ForeignKey(Forum, models.SET_NULL, null=True)
      title = models.CharField(max_length=32)
  
      def __str__(self):
keep keep keep keep replace keep keep keep keep keep
 Refs #23919 -- Removed python_2_unicode_compatible decorator usage
tests/null_fk_ordering/models.py