Check the Fritzing for wiring. There is a lot going on, so I couldn't think of a good way to show all of the wires. Click on wires and connections to see where everything goes.
There are some config options at the top of main.py.
nickmomrik/pi-multiplex-7-segment-displays
Multiplexing 7 Segment Common Cathode Displays on a Raspberry Pi
PythonGPL-3.0