从4.1.1升级到4.2.1的芹菜导致django.core.exceptions.ImproperlyConfigured：无法导入

Question

我之前使用的是celery 4.1.1版本，升级到4.2.1之后，celery开始引起

  

django.core.exceptions.ImproperlyConfigured：无法导入

这是我的 celery.py

import os
import sys
from celery import Celery
from django.apps import apps, AppConfig
from django.conf import settings


# set the default Django settings module for the 'celery' program.
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'config.settings.dev')  # pragma: no cover


app = Celery('app')
app.config_from_object('django.conf:settings', namespace='CELERY')


class CeleryConfig(AppConfig):
      name = 'app.taskapp'
      verbose_name = 'Celery Config'

      def ready(self):
          app.config_from_object('django.conf:settings', namespace='CELERY')
          app.autodiscover_tasks(lambda: settings.INSTALLED_APPS)

          if hasattr(settings, 'RAVEN_CONFIG'):
             # some code


     @app.task(bind=True)
     def debug_task(self):
         print('Request: {0!r}'.format(self.request))  # pragma: no cover

4.1.1完美运行。有什么建议吗？