Source for the torch.diff() operator

I would like to build a custom operator in c++ that is largely based on the torch.diff operator. I was trying to find the source code of that operator but github search failed me. Can anyone point me to the right source file please? Thank you!

/ I am also okay if someone can point me some documentation that explains the project structure and where one usually go for different parts /

Found it here: pytorch/ReduceOps.cpp at v1.13.1 · pytorch/pytorch · GitHub