Adding support for loops (#70209)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/70209
Test Plan: Imported from OSS
Reviewed By: anjali411
Differential Revision: D33555889
Pulled By: Gamrix
fbshipit-source-id: f6c0c9d517849e3679e07ac1c8cf3bf367e91882
