[WIP] data2vec jax
Author: BirgerMoell
Pull request: yes

# What does this PR do?
This adds data2vec flax model. Work in progress, just an initial draft.
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@sanchit-gandhi 

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Comments:
_The documentation is not available anymore as the PR was closed or merged._

Hey @BirgerMoell, thanks for jumping on this so quickly! Looks like a solid start on getting the new Data2Vec2Audio feature extractor written in JAX. Feel free to ask me any questions, more than happy to lend a hand! :)

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md) are likely to be ignored.

Hey @BirgerMoell, thanks again for jumping in on this one! Am happy to help with the JAX/Flax model port - see my previous comment for how to efficiently copy over the skeleton code from FlaxWav2Vec2! If busy, let's maybe close this one for now and re-open when there's time to look into it a bit more?