First of all, thank you for taking the time responding to my questions!
Secondly, I created a new branch tapas_up_to_date that is more up-to-date with upstream/master in which I copied all the files I added and made more improvements.
Currently, all things of the checklist are done except for 2 things:


tokenization_tapas.py should be improved (help/opinions needed)
tests should be written appropriately (also help needed). Currently I’ve written test_modeling_tapas.py of which 20 tests pass and 6 fail, but testing out TapasForQuestionAnswering would require Pandas, which obviously cannot be added to Transformers as an extra dependency. I’ve currently mainly tested out this model in Google Colab (such as this one 1)by pip installing my branch. Note that pandas is not a dependency of the model itself, it’s a dependency to test out the model.

All the rest is done (docstrings are added including the model doc which I checked using make html, a special TableQuestionAnsweringOutput is defined, the BERT imports are replaced by original code blocks and the model still works, tapas has been added to the auto._.py files, the soft dependency on torch-scatter has been added in the __init__ of TapasModel,…)
You can find the branch here: https://github.com/NielsRogge/transformers/tree/tapas_up_to_date 2
Could you maybe check out my work (or point me to someone) to get some feedback? I don’t really know if my code is meeting the quality standards of Transformers to make a PR.
Thank you!