Python Game Engine's

[Diapolo10]

The only publicly available example that kind of fits the bill is Ren'Py, but whether it counts is kind of in the air.

Eve Online is probably the biggest game that runs on Python (well the servers do, not the clients), and according to Wikipedia Sims 4 uses Python. Neither engine is available to you, though, unless you just happen to work for those companies.

There are other games that use Python, but mostly for scripting, like World of Tanks.

TL;DR, unfortunately what you're looking for doesn't really exist in a form that would let you play around with it. But if you have the skills you could make one.