Looks like everything works except the Gateway. Jupyter Gateway won’t work on Google Colab since they don’t expose REST API endpoints. You’ll have to set up your Jupyter environment locally. This way you can run the Gateway and point your browser to localhost.

This is the case for Flask as well. You can train your model in Google Colab but you have to then export the model and do inference on a local machine (or your own server instance like Digital Ocean).