题意：对于OpenAI Gym，是否有支持它的算法库？

问题背景：

OpenAI has released a new library called Gymnasium which is supposed to replace the Gym library. There are many libraries with implamentations of RL algorithms supporting gym environments, however the interfaces changes a bit with Gymnasium. Are there any libbraries with algorithms supporting Gymnasium? I tried CleanRL, KerasRL, RLib and some others and none of them work, the only way for now is to implement them manually, am I correct?

OpenAI 发布了一个名为 Gymnasium 的新库，旨在取代 Gym 库。有许多库实现了支持 Gym 环境的强化学习算法，但 Gymnasium 的接口稍有变化。有支持 Gymnasium 的算法库吗？我尝试了 CleanRL、KerasRL、RLib 和其他一些库，都无法正常工作，目前唯一的办法是手动实现这些算法，我说得对吗？

问题解决：

Stable Baselines3 doesn't have a release with Gymnasium support yet, but this pull request explains how to install and use it with gymnasium.

Stable Baselines3 尚未发布支持 Gymnasium 的版本，但这个拉取请求解释了如何安装并与 Gymnasium 一起使用它。

First install the version for that PR:

首先安装该拉取请求的版本：

$ pip install git+https://github.com/carlosluis/stable-baselines3@fix_tests

And assuming you have gymnasium installed already, you can run:

假设你已经安装了 gymnasium，你可以运行：

# Important step to override `gym` as `gymnasium`.
import sys
import gymnasium
sys.modules["gym"] = gymnasium

# Sample code which works
from stable_baselines3 import PPO
env = gymnasium.make("CartPole-v1", render_mode="rgb_array")
model = PPO("MlpPolicy", env, verbose=1)