This project is a blast from the past - 70+ years in the past, to be exact. The Enigma machine was a revolutionary encryption device that is considered to this day to be the greatest cryptic challenge humanity ever faced.
This program is a virtual "replica" of the Enigma. I say this within quotation marks because it is not, and not intended to be an exact replica. This machine in much more secure and just as simple.
Interested? Explore it yourself!
The main module in the file is enigma.py, it contains the main class - Enigma, which is a representation of the enigma machine. All the classes and functions have docstrings so you should be good to go from there!
PS: If you don't happen to know the specifics of how the Enigma works and how it is assembled, you should read this page from Wikipedia which should contain all the information you need.
Good Luck!