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Related Issues and Possible Duplicates

Description

https://docs.celeryproject.org/en/stable/userguide/extending.html#extending-commandoptions

The described code no longer works in celery 5+

Looking at celery's source code, 'user_options' are now expected to be a set(). In fact they are initialized to a defaultdict(set())

I believe that one should provide a click.option, but when i tried that things still fell apart as click is later accessing whatever is provided.opts

Suggestions

Upgrade the documentation to support click or modify the code to allow the above example to work