Donut high-level overview. Taken from the original paper. 
This model was contributed by nielsr. The original code can be found
here.
Usage tips

The quickest way to get started with Donut is by checking the tutorial
  notebooks, which show how to use the model
  at inference time as well as fine-tuning on custom data.
Donut is always used within the VisionEncoderDecoder framework.