Hey @rashub , sorry just seeing this!
FastHugs is quite out of date at this point, I would recommend using the Blurr library for HuggingFace + fastai GitHub - ohmeow/blurr: A library that integrates huggingface transformers with version 2 of the fastai framework 1
The fastai docs also have GPT2 + fastai example too in case you hadn’t seen:
  
      
      docs.fast.ai
  
  
    

Tutorial - Transformers | fastai

An example of how to incorporate the transfomers library from HuggingFace with fastai