transformers pytorch big_bird question-answering DocVQA Document Question Answering Document Visual Question Answering en dataset:rubentito/mp-docvqa arxiv:2212.05935 arxiv:1905.13648 base_model:google/bigbird-base-trivia-itc base_model:finetune:google/bigbird-base-trivia-itc license:gpl-3.0 endpoints_compatible region:us