Documentation enhancement - model_type
# 🚀 Feature request


Please provide a clear explanation of what the valid values would be for "model_type".  I think that the answer is any model name you would use in from_pretrained() but I am not sure.

## Motivation

Clarity of the parameter and saving time on trial and error and guesswork.

## Your contribution

If the assumption above is correct, I am willing to write up the answer if it will help.  If you have a HTML page with the list of valid values (maybe on a model page) we can just add a link to that.


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/master/CONTRIBUTING.md) are likely to be ignored.