gym.error.UnregisteredEnv: No registered env with id: meme-v0

[HRYEJJKUK]

Using gym in python, using my own defined environment:meme-v0. But it keeps reporting an error:gym.error.UnregisteredEnv: No registered env with id: meme-v0


Here are my attachments:
ExpressLanes_Deep-RL-master.zip
Once open, you can run it directly using cmd.exe and typing: python spinup/algos/vpg/vpg.py --env meme-v0 --steps 240 --epochs 100 --exp_name LBJ --seed 200 --objective RevMax.

[pseudo-rnd-thoughts]

Have you registered the environment before it is created?
You can check the registry variable