GNN实例.ipynb issue

[Leeable]

when i run :
train_loss, train_acc, test_acc = train(node_list=list(map(lambda x:x[0], N)),
edge_list=E,
label_list=list(map(lambda x:x[1], N)),
T=5)
the error shows like below:
RuntimeError: one of the variables needed for gradient computation has been modified by an inplace operation: [torch.FloatTensor [2, 2]], which is output 0 of TBackward, is at version 2; expected version 1 instead. Hint: enable anomaly detection to find the operation that failed to compute its gradient, with torch.autograd.set_detect_anomaly(True).

pytotch 1.8.0