Any plan to include BART and T5? 
# 🌟New model addition

## Model description

<!-- Important information -->

## Open Source status

* [ ] the model implementation is available: (give details)
* [ ] the model weights are available: (give details)
* [ ] who are the authors: (mention them)

## Additional context

<!-- Add any other context about the problem here. -->

please search for issues beforehand (and fill the template if there's not already a relevant issue)