PongNoFrameskip Environment Error

The error message indicates that the environment 'PongNoFrameskip-v4' does not exist in your Gym installation. Here are some possible reasons and fixes:

1. Check Gym Installation

Ensure you have installed Gym properly, along with the Atari environments:

bash
pip install gym[atari]
pip install gym[accept-rom-license]

or for newer versions:

bash
pip install gymnasium[atari]
pip install gymnasium[accept-rom-license]

If you're using Gymnasium instead of Gym, update your code:

python
import gymnasium as gym

2. Check Available Environments

List all available Gym environments to confirm if 'PongNoFrameskip-v4' exists:

python
import gym
print(gym.envs.registry.keys())

If 'PongNoFrameskip-v4' is missing, try using another available version, like:

python
env = gym.make('ALE/Pong-v5')

or

python
env = gym.make('Pong-v0')

3. Ensure ROMs Are Installed

Atari environments require ROMs. If they are missing, try installing them manually:

bash
pip install ale-py
ale-import-roms /path/to/roms

For Gymnasium, use:

bash
pip install gymnasium[atari]
pip install gymnasium[accept-rom-license]

Then try running your script again.

Let me know if the issue persists!