James Payne - Beginning Python: Using Python 2.6 and Python 3.1

Contents

Beginning Python: Using Python 2.6 and Python 3.1

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Copyright 2010 by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-0-470-41463-7

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To my patient and loving wife, Whitney, who believed in me before I did. And to my parents, Ronnie and Sharon Payne, who raised me to believe I could do anything I put my mind to, even when I told them I wanted to be Santa Claus. For my brother, Ron, who read my work even when it was bad, Dorjan, Eric, Clem, and Nick because they know things about me and will tell them if I dont include them.

About the Author

James Payne (Margate, FL) is Editor-in-Chief of Developer Shed, Inc. and has been writing and programming since the age of seven years old. Proficient in many languages, he has written over 400 articles covering practically every major programming language. As a contractor, he develops proprietary software for the financial industry using Python and likes to dabble in Django in his spare time.

Credits

Executive Editor

Carol Long

Project Editor

Ed Connor

Technical Editor

Chris McAvoy

Production Editors

Amy Weintraub and Tim Tate

Copy Editor

Kim Cofer

Editorial Director

Robyn B. Siesky

Editorial Manager

Mary Beth Wakefield

Marketing Manager

David Mayhew

Production Manager

Tim Tate

Vice President and Executive Group Publisher

Richard Swadley

Vice President and Executive Publisher

Barry Pruett

Associate Publisher

Jim Minatel

Project Coordinator, Cover

Lynsey Stanford

Proofreaders

Scott Klemp and Kristy Eldredge, Word One

Indexer

Ron Strauss

Cover Image

istockphoto.com/Frank_U

Acknowledgments

I would like to acknowledge the gang at Developer Shed: Jack and Jay Kim, whose constant hatred is an inspiration, Charles Fagundes, who made me an editor and not just a writer, Keith Lee, who provided coding support, and a special thanks to Jenny Ruggieri, who got me the job that got me this book. Lastly, Id like to thank all of the people that worked on the previous editions of this book for laying the groundwork, and the Editors Carol Long, Jenny Watson, Ed Connor, and Chris McAvoy who helped me meet deadlines no matter how much I didnt want to.

I would also like to acknowledge Guido Von Rossum, without whom there would be no language to write about.

Introduction

Welcome to Python 3.1!

Ive been working with Python for about ten years now, and every new version has caused me to fall in love with the language all over again. Version 3.1 is no different. If you are new to Python, rest easy Ill guide you every step of the way. If, on the other hand, you are an old Python hand exploring the new version, the book is structured so that you can learn the new information you need, without wasting time on already-known information.

I wanted to write this book because I love Python. I love it! And I want to share my love with you. And, maybe youll grow to love it as I do.

Who This Book Is For

If youre computer-literate, and want to learn a fun programming language to better control your computer, this book is for you.

If you are a system administrator who wants to learn a great language to help you better manage and configure systems and networks, this book is for you.

If you already know Python, but are wondering what cool new features are available in version 3.1, this book is for you.

In summary, this book is for anyone interested in exploring Python programming with the newest and most full-featured, easy-to-use version, 3.1.

What This Book Covers

This book is designed to cover Python 3.1. Python 3.1, released in 2009, is the latest major revision of the Python programming language. Since Python is a cross-platform language, the content and examples in the book are applicable in any platform (unless specified otherwise). When there is a choice to be made as to platform independence, the examples will be as cross-platform as possible.

In addition, since Python 3.1 is relatively new, not all supporting libraries have been updated to work in Python 3.x. In those instances where this is the case and it is felt that the theory still needs to be expounded upon, Python 2.6 will be used in lieu of version 3.1.

How This Book Is Structured

As might be expected from a Beginning book, the book begins with an introduction to the language. From there, youll move through the core of the language, then move on to more advanced and specialized topics. The book is divided up into four parts.