chainermn_distributed_cifar10.ipynb failed CI

Link to the notebook:
https://github.com/aws/amazon-sagemaker-examples/blob/master/sagemaker-python-sdk/chainer_cifar10/chainermn_distributed_cifar10.ipynb

Error:

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Exception encountered at "In [2]":
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ModuleNotFoundError Traceback (most recent call last)
in
----> 1 import chainer
2
3 from chainer.datasets import get_cifar10
4
5 train, test = get_cifar10()

ModuleNotFoundError: No module named 'chainer'

Open sagemaker-python-sdk/chainer_cifar10/chainermn_distributed_cifar10.ipynb and inspect the failing In [2] cell, then check how its CI environment provides dependencies. Confirm that the notebook can import chainer and complete its CI run without the reported ModuleNotFoundError.

Written by the indexing model from the issue text.