The Modern Physics Computational Assignment is available as a .py or a .txt. Of course, they work the same, the .py is just nicely color coded here and should (!) open with python. It's written in Python 3.x, for what it's worth. The program itself was created for a fictional scenario in which a civilization accelerates all their babies so that at some point they are all the same age and are not disadvantaged by different birth dates. It's a simple math based entirely on time dilation from special relativity.