LLamaQaStoppingCriteria not in transformers.generation.stopping_criteria?

[li-yang23]

I just checked codes in generation.py and I noticed it import LLamaQaStoppingCriteria from transformers.generation.stopping_criteria. However I did not find this function (or class) in the transformers/generation/stopping_criteria.py script. (not from the transformers installed by pip nor in this repo), may be it comes from another dependency?