I'm interested in switching out the [default keras NNs](https://github.com/philtabor/Youtube-Code-Repository/blob/1ef76059bf55f7df9ccc09fce0e0bfb7c13e89bd/ReinforcementLearning/PolicyGradient/PPO/tf2/networks.py) for catboost or other non NN models. Any guidance on how to accomplish it highly appreciated.