old_contents: # -*- coding: utf-8 -*-
  
  from django.db import models
  
  
  class ExampleModel(models.Model):
      name = models.CharField(max_length=15)
      value = models.BooleanField(default=False)
      date_created = models.DateTimeField(auto_now_add=True)
      related = models.ForeignKey("RelatedModel", blank=True, null=True, on_delete=models.CASCADE)
      relateds = models.ManyToManyField("RelatedM2MModel", blank=True)
  
      def __str__(self):
          return "ExampleModel %d" % (self.pk,)
  
      def __repr__(self):
          return "<ExampleModel: %d:'%s'>" % (
              self.pk,
              self.name,
          )
  
      def get_absolute_url(self):
          return "#{pk}".format(pk=self.pk)
  
      def get_negative_pk(self):
          return -1 * self.pk
  
  
  class RelatedModel(models.Model):
      name = models.CharField(max_length=15)
  
      def __str__(self):
          return "RelatedModel %d" % (self.pk,)
  
      def get_absolute_url(self):
          return "#{pk}".format(pk=self.pk)
  
  
  class RelatedM2MModel(models.Model):
      name = models.CharField(max_length=15)
  
  
  class ReverseRelatedModel(models.Model):
      name = models.CharField(max_length=15)
      example = models.ForeignKey("ExampleModel", on_delete=models.CASCADE)
  
new_contents: # -*- coding: utf-8 -*-
  
  from django.db import models
  
  
  class ExampleModel(models.Model):
      name = models.CharField(max_length=64)
      value = models.BooleanField(default=False)
      date_created = models.DateTimeField(auto_now_add=True)
      related = models.ForeignKey("RelatedModel", blank=True, null=True, on_delete=models.CASCADE)
      relateds = models.ManyToManyField("RelatedM2MModel", blank=True)
  
      def __str__(self):
          return "ExampleModel %d" % (self.pk,)
  
      def __repr__(self):
          return "<ExampleModel: %d:'%s'>" % (
              self.pk,
              self.name,
          )
  
      def get_absolute_url(self):
          return "#{pk}".format(pk=self.pk)
  
      def get_negative_pk(self):
          return -1 * self.pk
  
  
  class RelatedModel(models.Model):
      name = models.CharField(max_length=64)
  
      def __str__(self):
          return "RelatedModel %d" % (self.pk,)
  
      def get_absolute_url(self):
          return "#{pk}".format(pk=self.pk)
  
  
  class RelatedM2MModel(models.Model):
      name = models.CharField(max_length=15)
  
  
  class ReverseRelatedModel(models.Model):
      name = models.CharField(max_length=15)
      example = models.ForeignKey("ExampleModel", on_delete=models.CASCADE)
  
subject: Test fixes for MySQL