Is it possible to install cupy on google colab?

Edit: Google Colaboratory now provides Chainer, CuPy and iDeep by default. Manual installation is no longer necessary.

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Original Answer:

You can use a wheel to avoid building CuPy by yourself on Google Colab. Chainer officially provides snippet to install Chainer/CuPy on Google Colab.

!curl https://colab.chainer.org/install | sh -

We do not need to install cupy manually in Google colab. In Notebook Settings under Edit we can choose GPU. If you have chainer already installed you can confirm availability of cupy through this:

chainer.print_runtime_info()