While we have tried to provide all the code required to convey the book's ideas, we don't want to bore you with repetitive code snippets. Instead, we have created self-contained Jupyter notebooks (http://jupyter.org) that you can find via Git from https://github.com/PacktPublishing/Building-Machine-Learning-Systems-with-Python-Third-edition.
If you don't have Jupyter already, simply install it with pip install jupyter and then run it with jupyter notebook. It provides a much richer experience; for example, it directly integrates charts into it. Once you have cloned the Git repository of the book's code, you can simply follow along by hitting Shift + Enter. As a bonus, you will find that it has interactive widgets that let you play with the code: