Python 3 Object-oriented Programming Second Edition Unleash the power of Python 3 objects Dusty Phillips BIRMINGHAM - MUMBAI Python 3 Object-oriented Programming Second Edition Copyright © 2015 Packt Publishing All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews. Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book. Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information. First published: July 2010 Second edition: August 2015 Production reference: 1130815 Published by Packt Publishing Ltd. Livery Place 35 Livery Street Birmingham B3 2PB, UK. ISBN 978-1-78439-878-1 www.packtpub.com Credits Author Copy Editor Dusty Phillips Janbal Dharmaraj Reviewers Project Coordinator AMahdy AbdElAziz Neha Bhatnagar Grigoriy Beziuk Proofreader Krishna Bharadwaj Safis Editing Justin Cano Anthony Petitbois Indexer Claudio Rodriguez Hemangini Bari Commissioning Editor Graphics Edward Gordon Sheetal Aute Jason Monteiro Acquisition Editors Indrajit Das Production Coordinator Rebecca Pedley Komal Ramchandani Greg Wild Cover Work Komal Ramchandani Content Development Editors Divij Kotian Arvind Koul Anila Vincent Technical Editor Siddhi Rane About the Author Dusty Phillips is a Canadian software developer and author currently living in Seattle, Washington. He has been active in the open source community for a decade and a half and programming in Python for nearly all of it. He cofounded the popular Puget Sound Programming Python meetup group; drop by and say hi if you're in the area. Python 3 Object Oriented Programming, Packt Publishing, was the first of his books. He has also written Creating Apps In Kivy, O'Reilly, the mobile Python library, and self- published Hacking Happy, a journey to mental wellness for the technically inclined. He was hospitalized for suicidal tendencies shortly after the first edition of this book was published and has been an outspoken proponent for positive mental health ever since. About the Reviewers AMahdy AbdElAziz has more than 8 years of experience in software engineering using several languages and frameworks. Over the last 5 years, he has focused on Android and mobile development, including cross-platform tools, and Android internals, such as building custom ROMs and customizing AOSP for embedded devices. He is currently teaching Python at Information Technology Institution. You can visit his website, http://www.amahdy.net/, to find out more about him. Grigoriy Beziuk is a former CIO of Crowdage Foundation, acting as an independent software developer as this book was being written. He has worked with a wide variety of programming languages and technologies, including different versions of Python in different environments, ranging from purely scientific ones to modern production-scale web development issues. I would like to thank my mom, Larisa Beziuk, for giving me the gift of life; all of my teachers and friends for making my life more interesting; and all of my beloved ones, former and present for… well, everything. Krishna Bharadwaj is the cofounder of SMERGERS (https://www.smergers. com/), a Fintech start-up helping small and medium businesses raise capital from investors and different financial institutions. In the past, he has worked with early stage start-ups such as BlockBeacon (Santa Monica) and PricePoint (CA) and large organizations such as National Instruments, Bangalore, and Google, New York. Krishna got introduced to Python and FOSS during his college days and has continued to use it extensively in his personal projects and also professionally at work. Because of his liking for teaching and mentoring, he visits different universities, conducting workshops whenever he gets an opportunity. He holds a master's degree in computer science from the University of Southern California, Los Angeles, and a bachelor's degree in information science and engineering from the BMS College of Engineering, Bangalore. He can be reached through his e-mail, [email protected], or his website, http://www.krishnabharadwaj.info/. Justin Cano is a recent graduate from the University of California, Riverside, with a BS in computer engineering and is currently working as a software engineer in the Silicon Valley area with hopes of moving to a big tech company such as Google or Apple. He first started programming in the sixth grade, creating small, primitive websites in HTML and CSS. He started to learn computer science theory and C++ in his first year at UC Riverside and then started learning Python in his third year. Justin admits that at first, he wasn't immediately attracted to Python, since abstractions between C++ and Python are very different. It wasn't until he began to express more of an interest in coding contests and challenges that he began to show interest in Python, mainly because he feels that the readability and elegance of the Python syntax allows him to quickly and more naturally turn ideas and thought processes into Python code. He now writes Python code regularly, often to create mock-ups or prototypes of software applications before moving on to a more domain-specific language. I would like to thank the author for taking the time to write this book as I have received a lot of valuable insights and information on the Python language and design patterns. This book has strengthened my understanding of Python, and I believe that I am now a more knowledgeable Python programmer. Anthony Petitbois is an online architect in the video game industry with 13 years of professional experience in operations and development and more than 20 years of software development experience. He is passionate about new technologies and loves to take creative approaches to solve complex problems. In his spare time, he learns new languages and new platforms, plays video games, and spends time with his family in the beautiful region of British Columbia, Canada, where he now lives after emigrating from France in 2009. Claudio Rodriguez started working on PLCs for GE, but his main goal has always been research and development and turning dreams into reality. This made him move from automation engineering to software engineering and the structured way of software, OOD; the remote team working from the comfort of his computer was just too powerful not to take advantage of. During his master's, he got to learn the proper place to look for resources and found a friend in books and research papers and conferences. Eventually, he started working on a system to control an electric arc furnace, but the needs of his clients moved him into taking further control of technology. He has a deep love for complex AI and can be seen surrounded by papers, books, and a computer to test things, but he keeps things real by delivering beautiful and dynamic applications for his customers. www.PacktPub.com Support files, eBooks, discount offers, and more For support files and downloads related to your book, please visit www.PacktPub.com. Did you know that Packt offers eBook versions of every book published, with PDF and ePub files available? 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