pytorch

642afcb1 - Add sgn to torch.rst so that it appears in the built docs (#51479)

Add sgn to torch.rst so that it appears in the built docs (#51479) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/51479 Fixes https://github.com/pytorch/pytorch/issues/50146 Test Plan: Imported from OSS Reviewed By: mruberry Differential Revision: D26179734 Pulled By: anjali411 fbshipit-source-id: 1cda9a3dc9ce600e585900eea70fbecac0635d5c