deadline = datetime.datetime.now() - t
return cls(key_name=key_name, delete_when=deadline)

def put(self, **kwargs):

    def _tx():
        taskqueue.add(url='/admin/task/delete_page', countdown=delay,
            params={'path': key_name}, transactional=True)
return super(DeleteQueueItem, self).put(**kwargs)
if not self.is_saved():
    return db.run_in_transaction(_tx)
else:
    return super(DeleteQueueItem, self).put(**kwargs)
How to use a custom __init__ of an app engine Python model class properly?