Pybash is a python library to make python script as easy as in Bourne Again Shell (Bash).
Bash scripting is very easy to setup. So we end up using it all the time for simple procedural script.
Sometimes is it useful to have idempotent script, like Ansible and Saltstack teach use, this script should only do an action if needed.
Some tima ago, I have the need to convert a bunch of projects from ant (2004 stuff) to gradle. It was a very hard work, and imple bash scripting was not up to the task.
Python run, fix, rerun cycle was faster then groovy and I know python a way lot better.
There are other projects like doit, but mine is easier to use and follow a minimalistic apprach: only one file needed to do everything.