Adding the following lines to cloud/celery.py:
import celery
print celery.__file__
gave me the file itself and not the celery module from the library. After renaming celery.py to celeryapp.py and adjusting the imports all errors were gone.
Note:
That leads to a change in starting the worker:
celery worker --app=cloud.celeryapp:app
For those running celery==3.1.2 and getting this error:
TypeError: unpack_from() argument 1 must be string or read-only buffer, not memoryview
Apply the patch mentioned here: https://github.com/celery/celery/issues/1637