We do indeed use Unity! Somehow I was aware of ml-agents, but didn't realize it was a "gymification" library. I thought it was a framework for running stuff within the Unity editor, but seeing that it allows things to be run from a normal python environment, that's awesome. Thanks for making me look at the README and documentation closer.

And here I was thinking I would need to write a native dll wrapper or wait till my next game project to include necessary bits from the outside.