How to print the progress of a list comprehension in python?

Question

In my method i have to return a list within a list. I would like to have a list comprehension, because of the performance since the list takes about 5 minutes to create.

Answer 1

doc_collection = [[1, 2],
                  [3, 4],
                  [5, 6]]

result = [print(progress) or
          [str(token) for token in document]
          for progress, document in enumerate(doc_collection)]

print(result)  # [['1', '2'], ['3', '4'], ['5', '6']]

I don't consider this good or readable code, but the idea is fun.

It works because print always returns None so print(progress) or x will always be x (by the definition of or).