This app simply allows you to open an image, select a square region, and then save it to file. It is written with wxPython_Phoenix in Python 3.
The Program's entry point is SquareCrop.py. The only dependency is wxPython_Phoenix. You can run the script by running SquareCrop.py; put the scripts in a folder, make a setup file and install it with pip; or pass it into PyInstaller or something to create an executable app.
Copyright 2016 Tianyi Cao, I guess.