Fixed to_folder not saving dtype (#69983)
Summary:
As above.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/69983
Reviewed By: pbelevich, ngimel
Differential Revision: D33466529
Pulled By: Chillee
fbshipit-source-id: 2d2f0ad5b8e2492aba4c19fa034c8b6c0848a568
