The error comes from the torchvision itself:
attribute 'downsample' of type 'NoneType' is not usable in a script method (did you forget to add it __constants__?):
at /nfs/engine/rajagopalar/anaconda3/envs/torchExp/lib/python3.6/site-packages/torchvision/models/resnet.py:109:12
        out = self.relu(out)

Original post is here --> original post 9
Thanks in advance!