This program prompts the user to enter two IP addresses and a corresponding subnet mask. There are multiple versions of this program (2.0 being the latest). Version 2.0 was mainly geared towards simplifying the original version.
A tutorial that explains the development process to version 2 can be found here:
https://cybr.com/programming-languages-archives/how-i-made-my-python-subnet-calculator-more-efficient-with-40-less-code/