Flask Celery 异步任务配置 backend 还是报错 AttributeError: 'DisabledBackend' object has no attribute '_get_task_meta_for'

[bmos]

问题很明显，网上搜到的结果也都是说配置 backend，但是我觉得已经配置上了 首先用的是《深入理解 Flask 》中的例子，用 rabbitmq，报错。

CELERY_BROKER_URL = "amqp://guest:guest@localhost:5672//"  
CELERY_BACKEND_URL = "amqp://guest:guest@localhost:5672//"

启动后显示

• ** ---------- [config]
• ** ---------- .> app: webapp:0x7fb0f99e40b8
• ** ---------- .> transport: amqp://guest:**@localhost:5672//
• ** ---------- .> results: amqp://
• *** --- * --- .> concurrency: 12 (prefork) -- ******* ---- .> task events: OFF (enable -E to monitor tasks in this worker) --- ***** ----- -------------- [queues] .> celery exchange=celery(direct) key=celery

尝试了 redis
CELERY_BROKER_URL = "redis://localhost:6379/0"
CELERY_BACKEND_URL = "redis://localhost:6379/0"
启动后显示

• ** ---------- [config]
• ** ---------- .> app: webapp:0x7f91ac94b668
• ** ---------- .> transport: redis://localhost:6379/0
• ** ---------- .> results: redis://localhost:6379/0
• *** --- * --- .> concurrency: 12 (prefork) -- ******* ---- .> task events: OFF (enable -E to monitor tasks in this worker) --- ***** ----- -------------- [queues] .> celery exchange=celery(direct) key=celery

毫无意外都是显示 DisabledBackend 错误

按照我的尿性，通常会打错字母，这次已经看了一天了，没有错字母。只能发个帖求助。╮(╯▽╰)╭，各位大佬走过路过看一看。