Unable to convert output to interpretable format
# 🚀 Feature request
There is no way to convert model outputs to a human-interpretable format, such as a list of token strings. Without this feature, there is no practicality other than benchmarking model performance, which does not require such a feature.

## Motivation
I'm trying to use the T5 CoLA task to determine whether an input sentence is grammatical.

## Your contribution
See #12969 
