pytorch

70f886ff - Revert D18253777: Remove observer module after insert_quant_dequant

Revert D18253777: Remove observer module after insert_quant_dequant Test Plan: revert-hammer Differential Revision: D18253777 Original commit changeset: 26081c4c3fd3 fbshipit-source-id: 88f330c34976030c9310e7982fa6ae74e093ebbf