old_contents: from django.db import models
  
  # Create your models here.
  
new_contents: import datetime
  
  from django.db import models
  from django.utils import timezone 
  
  # Create your models here.
  class TodoList(models.Model):
      name        = models.CharField()
      # author      = models.ForeignKey("User")
      create_time = models.DateTimeField(auto_now_add=True)
  
  
      def __unicode__(self):
          return self.name
  
  
  class TodoItem(models.Model):
      content     = models.CharField()
      todo_list   = models.ForeignKey(TodoItem)
  
      def __unicode__(self):
          return self.content
  
  
  
subject: make basic model