Hi,
BatchNormBackward is different from the python Function because it is implemented purely in C++.
The goal of these C++ functions is to be able to run computations without having to deal with python (and especially the GIL), so it is expected to you cannot modify them from python.
You can still associate hooks to them as any other function with the register_hook() method.
The .creator has been changed to .grad_fn in master, you can look here for how to traverse the graph: https://github.com/szagoruyko/functional-zoo/blob/master/visualize.py 20