Book Image

The Python Apprentice

By : Robert Smallshire, Austin Bingham
Book Image

The Python Apprentice

By: Robert Smallshire, Austin Bingham

Overview of this book

Experienced programmers want to know how to enhance their craft and we want to help them start as apprentices with Python. We know that before mastering Python you need to learn the culture and the tools to become a productive member of any Python project. Our goal with this book is to give you a practical and thorough introduction to Python programming, providing you with the insight and technical craftsmanship you need to be a productive member of any Python project. Python is a big language, and it’s not our intention with this book to cover everything there is to know. We just want to make sure that you, as the developer, know the tools, basic idioms and of course the ins and outs of the language, the standard library and other modules to be able to jump into most projects.
Table of Contents (21 chapters)
Title Page
Credits
About the Authors
www.PacktPub.com
Customer Feedback
Preface
12
Afterword – Just the Beginning

The Python execution model


In order to have a really solid foundation in Python, it's important to understand the Python  execution model. By this, we mean the rules defining precisely when function definitions and other important events occur during module import and execution. To help you develop this understanding, we'll focus on the def keyword since you're already familiar with it. Once you have an understanding of how def is processed by Python, you'll know most of what you need to know about Python's execution model.

What's important to understand is this: def isn't merely a declaration, it's a statement. What this means is that def is actually executed at runtime along with the rest of the top-level module-scope code. What def does is to bind the code in the function's body to the name following def. When modules are imported or run, all of the top-level statements are run, and this is the means by which the functions within the module namespace are defined.

To reiterate, def is executed...