[BUG] - <title> Error in downloading MuJoCo Gymnasium library

[radhika-singh-10]

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Getting this error - MuJoCo is not installed, run pip install "gymnasium[mujoco]"

while running this doc -
https://docs.pytorch.org/tutorials/intermediate/reinforcement_ppo.html

Describe the bug

This command is giving error-!pip3 install gym[mujoco]
Unable to run this code as a result - base_env = GymEnv("InvertedDoublePendulum-v4", device=device)

Describe your environment

Platform - MacOS, Google Colab
CPU
pytorch version-2.6.0+cu124

[abhitorch81]

✅ A fix has been proposed in PR #3401: Fix PPO tutorial for gymnasium and Mujoco rendering compatibility in Colab

This PR:

• Adds support for both gymnasium and gym
• Dynamically selects InvertedDoublePendulum-v5 or v4
• Adds MUJOCO_GL=osmesa for safe Mujoco rendering in Google Colab

Once merged, this should resolve the issue.