Early_stopping in openNMT-py

I’m trying to OpenNMT-py training
What is correct configure for setting early_stopping and early_stopping_criteria options
–early_stopping 10?
–early_stopping_criteria acc ppl?

I’d not found opennmt-py docs
anyone who did correct config…?

You can refer to the pull request that introduced the feature:

Thank to your reply, I resolve them…!