Add the Bamba Model
Author: fabianlim
Pull request: yes
Labels: name: New model

name: run-slow

name: State space models

# What does this PR do?

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This PR merges the `BambaModel`, which is a hybrid [mamba2](https://github.com/state-spaces/mamba) architecture with SwiGLU. The checkpoints are  jointly trained by IBM, Princeton, and UIUC.

The implementation is based off  [ai21labs/Jamba-v0.1](https://huggingface.co/ai21labs/Jamba-v0.1) and the mamba2 implementation ported over to HF for the codestral model.

cc: @ani300, @raghukiran1224 

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Models:

- text models: @ArthurZucker
- vision models: @amyeroberts, @qubvel
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- flax: @sanchit-gandhi
- generate: @zucchini-nlp (visual-language models) or @gante (all others)
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- tokenizers: @ArthurZucker
- trainer: @muellerzr and @SunMarc
- chat templates: @Rocketknight1

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Comments:
Hi @fabianlim, do you have a paper reference for this model or any details on the trained checkpoints?

@Rocketknight1 thanks for reaching out. Yes my colleagues are preparing a paper and a GitHub repo with the (training) code. And checkpoints will be 1.8T, 2T, 2.2T, and an sft model. We will update the PR accordingly. 

cc: @raghukiran1224

The data used is all open, we plan to share any and all details on what the community would want! Open source is the name of the game 😄 

Cool! @molbap will be the point of contact at Hugging Face for this PR, so feel free to ping me or him if you have any questions as you're working on it.

Kudos! 🚀