distilbert-flax
Author: kamalkraj
Pull request: yes

# What does this PR do?
DistilBert Flax

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Comments:
Great Great job @kamalkraj! 

Think the only major thing to update is to docs in the modeling file (at the moment it looks like it's the PyTorch docs, but should be Flax :-)) 



@patrickvonplaten 
Thanks for the review.
Done changes according to your review. 

Hi @kamalkraj , I'm also really interested in that PR - thanks for adding it :hugs: 

Do you also plan to add a script for the distillation process (like it is done in the ["old" script](https://github.com/huggingface/transformers/tree/master/examples/research_projects/distillation)), as I would like to re-distillate some of my previous DistilBERT models (I don't have access to multi GPU setups, only to TPUs at the moment).

Hi @stefan-it,

I will go through the scripts and pings you. 
I have multi-GPU access. Which TPU do you use? v3-8 ?

```
JAX_PLATFORM_NAME=cpu RUN_SLOW=1 pytest tests/test_modeling_flax_distilbert.py::FlaxDistilBertModelIntegrationTest::test_inference_no_head_absolute_embedding
```

passes and the code looks good :-) Ready to merge IMO :tada: ! 

@patil-suraj the slow test doesn't pass on TPU since distilbert has pretty extreme activations in the forward pass like a couple of other models. We need to think a bit how to adapt the slow test depending on whether they're run on TPU or not in general...

Great work @kamalkraj !