Hypermodern Python Tooling

Chapter 1. Installing Python

If you’ve picked up this book, you likely have Python installed on your machine already. Most common operating systems ship with a python3 command. This can be the interpreter used by the system itself; on Windows and macOS, it’s a placeholder that installs Python for you when you invoke it for the first time.

Why dedicate an entire chapter to the topic if it’s so easy to get Python onto a new machine? The answer is that installing Python for long-term development can be a complex matter, and there are several reasons for this:

• You generally need multiple versions of Python installed side by side. (If you’re wondering why, we’ll get to that shortly.)

• There are a few different ways to install Python across the common platforms, each with unique advantages, tradeoffs, and sometimes pitfalls.

• Python is a moving target: you need to keep existing installations up-to-date with the latest maintenance release, add installations when a new feature version is published, and remove versions that are no longer supported. You may even need to test a prerelease of the next Python.

• You may want your code to run on multiple platforms. While Python makes it easy to write portable programs, setting up a developer environment requires some familiarity with the idiosyncrasies of each platform.

• You may want to run your code with an alternative implementation of Python.¹

In this first chapter, I’ll show you how to install multiple Python versions on some of ...