pytorch

b1b77148 - Back out "[Gradient Compression] Surface C++ comm hooks to Python API as built-in comm hooks" (#47234)

Back out "[Gradient Compression] Surface C++ comm hooks to Python API as built-in comm hooks" (#47234) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/47234 Revert the diff because of https://github.com/pytorch/pytorch/issues/47153 Original PR issue: C++ DDP Communication Hook https://github.com/pytorch/pytorch/issues/46348 ghstack-source-id: 115720415 Test Plan: waitforbuildbot Reviewed By: mrshenli Differential Revision: D24691866 fbshipit-source-id: 58fe0c45943a2ae2a09fe5d5eac4a4d947586539