Import hipify_python only when needed (#4031)
Import hipify_python only when needed (#4031)

Do this after the version check to avoid failures on import for earlier
torch where that module did not exist.
See #3901

Co-authored-by: Vasilis Vryniotis <d748cd3f763058dcf20e5489b9bc2373b78db68c@users.noreply.github.com>
pytorch/vision,pytorch/vision,pytorch/vision,pytorch/vision,pytorch/vision,pytorch/vision