Whenever you see a triple "Greater Than" operator like this >>> used here, know that this is the interactive way to use Python, and would be typed into a command prompt. To recreate this for yourself you would first need Python installed, open a command prompt and type "python" (or perhaps "python3" if you have multiple versions of Python installed or simply want to be specific) and it would open with the following (or something similar to it depending on your system and the Python version you have installed):
Python 3.7.0 (v3.7.0:1bf9cc5093, Jun 27 2018, 04:59:51) [MSC v.1914 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>>
You would see a blinking cursor to the right of the >>> and be allowed to type Python code and have it executed in real time, perfectly analogous to what you would be used to with the interactivity available with the Immediate Window in the VBE.