demo pytorch_graph.ipynb not working

[arodriguezca]

Hello

I'm installed via pip on 02/05/2021, and using torch==1.7.1, demo pytorch_graph.ipynb doesn't work.

Error:
RuntimeError: Only tuples, lists and Variables supported as JIT inputs/outputs. Dictionaries and strings are also accepted but their usage is not recommended. But got unsupported type NoneType