cannot import name 'EPISODE_RETURN_MEAN' from 'ray.rllib.utils.metrics'

[luweiagi]

What happened + What you expected to happen

~/ray/rllib/examples# python cartpole_lstm.py

Traceback (most recent call last):
  File "/root/autodl-tmp/ray/rllib/examples/cartpole_lstm.py", line 9, in <module>
    from ray.rllib.utils.metrics import (
ImportError: cannot import name 'EPISODE_RETURN_MEAN' from 'ray.rllib.utils.metrics' (/root/miniconda3/envs/rllib/lib/python3.11/site-packages/ray/rllib/utils/metrics/__init__.py)

Versions / Dependencies

Python 3.11.9
ray 2.22.0

Reproduction script

Issue Severity

None