Where is the torchvision.ops.nms() method located?

I am looking for a method in torch, but for the love of god I can not not find the function definition!
The reason I need to find it is that I need to get rid of the torch dependency and I want to try to convert it into numpy.

I am speaking about torchvision.ops.nms()
This method is located in torchvision/ops/boxes.py and returns torch.ops.torchvision.nms().

This method is generated code which can be found in torch/_ops.py where they initialize ops with ops: _Ops = _Ops().

Thats the point where I am lost, the class is located in the same file, but I cant figure out which library it calls to get the nms() method.

Please help me :frowning:

The CPU kernel can be found here and the CUDA kernel can be found here.