pytorch

82174330 - [DataLoader2] Adding Messages, Protocols, Loop wrappers (#63882)

[DataLoader2] Adding Messages, Protocols, Loop wrappers (#63882) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/63882 Test Plan: Imported from OSS Reviewed By: ejguan Differential Revision: D30627452 Pulled By: VitalyFedyunin fbshipit-source-id: 561ea2df07f3572e04401171946154024126387b