pqdm.processes 'AttributeError' object is not iterable while it works with pdqm.threads

Question

I have a newbie python issue which I do not understand.

I have working code for parallel execution using pqdm. It works if I use from pqdm.threads import pqdm and fails with 'AttributeError' object is not iterable if I switch to from pqdm.processes import pqdm instead.

What is it that I do not understand here? What can be the problem here?

Thanks.