albert flax
Author: kamalkraj
Pull request: yes

# What does this PR do?

ALBERT Flax Model

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Fixes # (issue)


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Models:

- albert, bert, xlm: @LysandreJik
- blenderbot, bart, marian, pegasus, encoderdecoder,  t5: @patrickvonplaten, @patil-suraj
- longformer, reformer, transfoxl, xlnet: @patrickvonplaten
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- gpt2: @patrickvonplaten, @LysandreJik
- rag: @patrickvonplaten, @lhoestq
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Library:

- benchmarks: @patrickvonplaten
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- tokenizers: @n1t0, @LysandreJik
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Documentation: @sgugger

HF projects:

- datasets: [different repo](https://github.com/huggingface/datasets)
- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

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Comments:
@patrickvonplaten 
Done changes according to your suggestions.
Thanks for the review 

Hey @kamalkraj , thanks for that PR! Can't wait to road-test it  :hugs: 

I tried training several ALBERT models with the official implementation, but had no luck in training a good performing model.




> I tried training several ALBERT models with the official implementation, but had no luck in training a good performing model.

pre-training with TF 1 code?

Yeah, it was the TF 1 code base, and I've also trained various model sizes. Let's see if I have more luck using the FLAX implementation 😅

Awesome addition @kamalkraj - thanks a lot :-) Left a couple of final additions

@patrickvonplaten 
Done changes according to review.

Slow tests are passing on CPU - thanks for the model addition @kamalkraj !