Introducing DataChunk for DataPipes batching (#62768)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/62768
This is part of TorchArrow DF support preparation, separating it to multiple PRs to simplify review process.
Test Plan: Imported from OSS
Reviewed By: ejguan
Differential Revision: D30149090
Pulled By: VitalyFedyunin
fbshipit-source-id: a36b5ff56e2ac6b06060014d4cd41b487754acb8
