PR's welcome. ;)
Python makes sense for scripts that need good argument parsing, or complicated intermediate input processing. But it's pretty annoying to get a shell pipeline working in Python. `foo | bar | baz` is about 15 characters in bash.
Here's an example. I use `llbranch` all the time: https://github.com/shawwn/scrap/blob/master/llbranch
It lists all branches in a project. It's nicely colorized. What would the equivalent Python be? Who knows, but it'd be much longer.