HoverNet enums (Mode and Branch) are defined inside the HoverNet module, but it seems that this is not compatible with TorchScript and produce error. I have filed an issue for that on PyTorch repo: pytorch/pytorch#85813
Hopefully they can resolve this; however, regardless of that we should move these enums to monia/utils/enums similar to other keys. This will solve this issue and give a more standard way to defining keys.