PyPi is a Python package index (also known as a cheeseshop). Satin is a UI testing library that I have been tinkering with on and off while developing Herculeum. I have now released version 0.1.0 of Satin in PyPi, in order to make it easier for others to download it.
The change is reflected in requirements-dev file of Herculeum. Now it is possible to download almost all dependencies of the game in just a single command:
pypi install -r requirements-dev