python之结果后端中的 Celery + rabbitmq

任务.py:

from celery import Celery 
 
app = Celery('tasks', broker='amqp://guest@localhost//') 
 
@app.task 
def add(x, y): 
    return x + y 

调用.py:

from tasks import add 
 
result = add.delay(1, 4) 
 
result.ready() 

celeryconfig.py:(在同一目录下)

BROKER_URL = 'amqp://guest@localhost//' 
 
CELERY_RESULT_BACKEND = 'amqp://guest@localhost//' 
 
CELERY_TASK_SERIALIZER = 'json' 
 
CELERY_RESULT_SERIALIZER = 'json' 
 
CELERY_ACCEPT_CONTENT=['json'] 
 
CELERY_TIMEZONE = 'Europe/Oslo' 
 
CELERY_ENABLE_UTC = True 

在 call.py 我有一个错误:

AttributeError: 'DisabledBackend' object has no attribute '_get_task_meta_for'

我阅读了文档，我有结果后端，为什么它不起作用？如何解决？

谢谢!