Gym dependency will not install

[levmckinney]

Bug description

When attempting to install the gym dependency I get the following error:

  error: subprocess-exited-with-error
  
  × python setup.py egg_info did not run successfully.
  │ exit code: 1
  ╰─> [1 lines of output]
      error in gym setup command: 'extras_require' must be a dictionary whose values are strings or lists of strings containing valid project/version requirement specifiers.
      [end of output]
  
  note: This error originates from a subprocess, and is likely not a problem with pip.
error: metadata-generation-failed

× Encountered error while generating package metadata.
╰─> See above for output.

note: This is an issue with the package mentioned above, not pip.

Steps to reproduce

Attempt to install imitation from source with a setuptools version grater than 65 see openai/gym#3176

Environment

• Operating system and version: archlinux
• Python version: 3.8

Mitigation

This can be mitigated by downgrading to setuptools==65.5.0 as pointed out in openai/gym#3176 (comment).

[levmckinney]

It seems like the only long term solution here is to switch to gymnasium #666. Stablebaslines now uses gymnasium by default DLR-RM/stable-baselines3#1327. Continuing to use the unmaintained gym dependency is untenable long term.

[AdamGleave]

Closing in favor of #734