I try to give a simplest solution for the unexpected result of reversed in #1484 and #1588.
The functionality of the built-in function reversed should return a reversed iterator of the input.
However, the tqdm does not behave as the common behavior when warped with reversed.
The further detail of the are well-mentioned in the previous issues, #1484 and #1588.
I try to come up with a solution that requires the minimum modification of the original code, and small impact to the performance.
The solution is to use the standard library of Python, copy, to shallow copy the original object of the tqdm and replace the self.iterable by the reversed of it.
Hope this non-intuitive behavior can be changed.
Thanks.

P.S. Due to the unsigned commit in the previous PR, I open a new one.