# What does this PR do?

This PR creates the precedent of deprecating models in the library. By deprecating we indicate that we will stop maintaining such models, but there is no intention of actually removing those models and breaking support for them (they might one day move into a separate repo/on the Hub but we would still add the necessary imports to make sure backward compatibility stays). The main point is that we stop testing those models (to ease a bit the burden on our CI).

Deprecated models are moved in models/deprecated so direct import of objects from their modeling files will break (though that's easily fixed by adding the `.deprecated` in the path). They are removed from the `tests` folder and a mention is added in the doc page of the model.

The heuristic to pick the deprecated models in this PR is: models older than a year that got less than a cumulated 1,000 downloads (over all checkpoints) in the last 30 days (counting deduplicated downloads).
Deprecate models. # What does this PR do?

This PR creates the precedent of deprecating models in the library. By deprecating we indicate that we will stop maintaining such models, but there is no intention of actually removing those models and breaking support for them (they might one day move into a separate repo/on the Hub but we would still add the necessary imports to make sure backward compatibility stays). The main point is that we stop testing those models (to ease a bit the burden on our CI).

Deprecated models are moved in models/deprecated so direct import of objects from their modeling files will break (though that's easily fixed by adding the `.deprecated` in the path). They are removed from the `tests` folder and a mention is added in the doc page of the model.

The heuristic to pick the deprecated models in this PR is: models older than a year that got less than a cumulated 1,000 downloads (over all checkpoints) in the last 30 days (counting deduplicated downloads).
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# RetriBERT

## Overview

The RetriBERT model was proposed in the blog post [Explain Anything Like I'm Five: A Model for Open Domain Long Form
Question Answering](https://yjernite.github.io/lfqa.html). RetriBERT is a small model that uses either a single or
pair of BERT encoders with lower-dimension projection for dense semantic indexing of text.

This model was contributed by [yjernite](https://huggingface.co/yjernite). Code to train and use the model can be
found [here](https://github.com/huggingface/transformers/tree/main/examples/research-projects/distillation).


## RetriBertConfig

[[autodoc]] RetriBertConfig

## RetriBertTokenizer

[[autodoc]] RetriBertTokenizer

## RetriBertTokenizerFast

[[autodoc]] RetriBertTokenizerFast

## RetriBertModel

[[autodoc]] RetriBertModel
    - forward

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an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
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# RetriBERT

<Tip warning={true}>

This model is in maintenance mode only, so we won't accept any new PRs changing its code.

If you run into any issues running this model, please reinstall the last version that supported this model: v4.30.0.
You can do so by running the following command: `pip install -U transformers==4.30.0`.

</Tip>

## Overview

The RetriBERT model was proposed in the blog post [Explain Anything Like I'm Five: A Model for Open Domain Long Form
Question Answering](https://yjernite.github.io/lfqa.html). RetriBERT is a small model that uses either a single or
pair of BERT encoders with lower-dimension projection for dense semantic indexing of text.

This model was contributed by [yjernite](https://huggingface.co/yjernite). Code to train and use the model can be
found [here](https://github.com/huggingface/transformers/tree/main/examples/research-projects/distillation).


## RetriBertConfig

[[autodoc]] RetriBertConfig

## RetriBertTokenizer

[[autodoc]] RetriBertTokenizer

## RetriBertTokenizerFast

[[autodoc]] RetriBertTokenizerFast

## RetriBertModel

[[autodoc]] RetriBertModel
    - forward
