I can't tell you how many times I've kicked off a long running process only to kill it and add in a progress indicator. I probably should have come up with something standard awhile ago, but now I don't have to. tqdm has created one kind of solution.
Instantly make your loops show a progress meter - just wrap any iterator with
tqdm(iterator), and you're done!
Can't say much more about it, but if you have had this problem in the past you might want to check out tqdm.