The provided code doesn't seem self-contained, as if it would run just like that without modification. For example, where does 'num_lines' come from?

Edit: never mind. Ignore that. There is a link on the page which I overlooked, with a more complete example. https://gist.githubusercontent.com/tekknolagi/4bee494a6e4483...

Cool stuff. Now I'm eager to find a way to make this work for multiple tqdm progress bars, running in parallel.