Implemented loss for training AudioFrameClassification
Author: MorenoLaQuatra
Pull request: yes

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Fixes #17509 on WavLMForAudioFrameClassification model


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I think @anton-l or @patrickvonplaten


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_The documentation is not available anymore as the PR was closed or merged._

Hi @MorenoLaQuatra, thank you for the contribution! :hugs: 

As you may have seen, the `check_repository_consistency` test doesn't pass. That's because `WavLMForAudioClassification` is auto-copied from `Wav2Vec2ForAudioClassification` using this line: https://github.com/huggingface/transformers/blob/80bb27abb4710267a99443736bde44fe64724615/src/transformers/models/wavlm/modeling_wavlm.py#L1534
Could you please move the loss inside `Wav2Vec2ForAudioFrameClassification` and then run `make fix-copies` from the root of your `transformers` directory? Then your implementation will propagate to all of the models that support audio frame classification :slightly_smiling_face: 

Thank you @anton-l for pointing it out. I was not aware of the copy mechanism (sorry!). I think now it should be good, I modified `modeling_wav2vec2.py` and run `make fix-copies`. Let me know if something is missing.