old_contents: from django.db import models
  
  
  class OrderCreater(models.Model):
      id = models.BigIntegerField(primary_key=True)
  
      class Meta:
          abstract = True
  
  
  class Order(models.Model):
      creater_id = models.BigIntegerField(primary_key=True)
      create_by = models.CharField(max_length=255)
  
      @property
      def creater(self):
          for create_cls in OrderCreater.__subclasses__():
              if create_cls.Type == self.create_by:
                  return create_cls.objects.get(id=self.creater_id)
  
  
  class Manager(OrderCreater):
      Type = "Manager"
  
  
  class Customer(OrderCreater):
      Type = "Customer"
  
new_contents: from ycyc.collections.tagmaps import TagMaps
  from django.db import models
  
  
  class OrderCreater(models.Model):
      Creaters = TagMaps()
      id = models.BigIntegerField(primary_key=True)
  
      class Meta:
          abstract = True
  
  
  class Order(models.Model):
      creater_id = models.BigIntegerField(primary_key=True)
      create_by = models.CharField(max_length=255)
  
      @property
      def creater(self):
          create_cls = OrderCreater.Creaters.get(self.create_by)
          if create_cls.Type == self.create_by:
              return create_cls.objects.get(id=self.creater_id)
  
  
  @OrderCreater.Creaters.register("Manager")
  class Manager(OrderCreater):
      pass
  
  
  @OrderCreater.Creaters.register("Customer")
  class Customer(OrderCreater):
      pass
  
subject: update dynamic_link