Description of problem:

Chapter 9 of DEVELOPING AND DEPLOYING DATA MODELS mentions to run run_flask.ipynb notebook, but the source where readers can download that file from should be mentioned too.

Prerequisites (if any, like setup, operators/versions):

Steps to Reproduce

1. Go to Chapter 9 of DEVELOPING AND DEPLOYING DATA MODELS
2. check the procedure

Actual results:

mentions to run run_flask.ipynb notebook, but the source is not 

Expected results:

source where to find the sample notebook is mentioned

Reproducibility (Always/Intermittent/Only Once):

Build Details:

Workaround:

Additional info: