Add a way of generating a FunctionSchema from example values because hop's schema varies even for the same hop.
We didn't use torch._C.FunctionSchema because we cannot construct the classes directly (e.g. "__init__" cannot be used for torch._C.FunctionSchema). Also extending the Basic types in c++ seems not that easy.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/133521
Approved by: https://github.com/zou3519