[Bug Report] dgl_gcn example not working per readme

[veenapaddy]

Link to the notebook Replicating the readme files https://github.com/aws/amazon-sagemaker-examples/tree/main/sagemaker-python-sdk/dgl_gcn

Describe the bug After creation of the DGL_py36_pytorch1.2 environment, with pytorch backend, selecting the environment does not work (broken link symbol, and says the notebook server is not communicating).

To reproduce

# Clone python3 environment
conda create --name DGL_py36_pytorch1.2 --clone python3

# Install PyTorch and DGL
conda install --name DGL_py36_pytorch1.2 pytorch=1.2 torchvision -c pytorch
conda install --name DGL_py36_pytorch1.2 -c dglteam dgl-cuda10.0

then, open a notebook, select "conda_dgl_py36_pytorch1.2" as the kernel. This should replicate the error.

Logs If applicable, add logs to help explain your problem. You may also attach an .ipynb file to this issue if it includes relevant logs or output.