Learn Python Programming Second Edition The no nonsense beginner s guide to programming data science and web development with Python 3 7 Fabrizio Romano BIRMINGHAM MUMBAI Learn Python Programming Second Edition Copyright 2018 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 s nor Packt Publishing or its dealers and distributors will be held liable for any damages caused or alleged to have been 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 Commissioning Editor Richa Tripathi Acquisition Editor Karan Sadawana Content Development Editor Rohit Singh Technical Editor Romy Dias Copy Editor Safis Editing Project Coordinator Vaidehi Sawant Proofreader Safis Editing Indexer Mariammal Chettiyar Graphics Jason Monteiro Production Coordinator Shantanu Zagade First published December 2015 Second edition June 2018 Production reference 2241018 Published by Packt Publishing Ltd Livery Place 35 Livery Street Birmingham B3 2PB UK ISBN 978 1 78899 666 2 www packtpub com To my dear dear friend and mentor Torsten Alexander Lange Thank you for all the love and support mapt io Mapt is an online digital library that gives you full access to over 5 000 books and videos as well as industry leading tools to help you plan your personal development and advance your career For more information please visit our website Why subscribe Spend less time learning and more time coding with practical eBooks and Videos from over 4 000 industry professionals Improve your learning with Skill Plans built especially for you Get a free eBook or video every month Mapt is fully searchable Copy and paste print and bookmark content PacktPub com Did you know that Packt offers eBook versions of every book published with PDF and ePub files available You can upgrade to the eBook version at www PacktPub com and as a print book customer you are entitled to a discount on the eBook copy Get in touch with us at service packtpub com for more details At www PacktPub com you can also read a collection of free technical articles sign up for a range of free newsletters and receive exclusive discounts and offers on Packt books and eBooks Foreword I first got to know Fabrizio when he became our lead developer a few years ago It was quickly apparent that he was one of those rare people who combine rigorous technical expertise with a genuine care for the people around him and a true passion to mentor and teach Whether it was designing a system pairing to write code doing code reviews or even organizing team card games at lunch Fab was always thinking not only about the best way to do the job but also about how to make sure that the entire team had the skills and motivation to do their best You ll meet the same wise and caring guide in this book Every chapter every example every explanation has been carefully thought out driven by a desire to impart the best and most accurate understanding of the technology and to do it with kindness Fab takes you under his wing to teach you both Python s syntax and its best practices I m also impressed with the scope of this book Python has grown and evolved over the years and it now spans an enormous ecosystem being used for web development routine data handling and ETL and increasingly for data science If you are new to the Python ecosystem it s often hard to know what to study to achieve your goals In this book you will find useful examples exposing you to many different uses of Python which will help guide you as you move through the breadth that Python offers I hope you will enjoy learning Python and become a member of our global community I m proud to have been asked to write this but above all I m pleased that Fab will be your guide Naomi Ceder Python Software Foundation Fellow Contributors About the author Fabrizio Romano was born in Italy in 1975 He holds a master s degree in computer science engineering from the University of Padova He is also a certified scrum master Reiki master and teacher and a member of CNHC He moved to London in 2011 to work for companies such as Glasses Direct TBG Sprinklr and student com He now works at Sohonet as a Principal Engineer Team Lead He has given talks on Teaching Python and TDD at two editions of EuroPython and at Skillsmatter and ProgSCon in London I m grateful to all those who helped me create this book Special thanks to Dr Naomi Ceder for writing the foreword to this edition and to Heinrich Kruger and Julio Trigo for reviewing this volume To my friends and family who love me and support me every day thank you And to Petra Lange for always being so lovely to me thank you About the reviewers Heinrich Kruger was born in South Africa in 1981 He obtained a bachelor s degree with honors from the University of the Witwatersrand in South Africa in 2005 and a master s degree in computer science from Utrecht University in the Netherlands in 2008 He worked as a research assistant at Utrecht University from 2009 until 2013 and has been working as a professional software developer developer since 2014 He has been using Python for personal and projects and in his studies since 2004 and professionally since 2014 Julio Vicente Trigo Guijarro is a computer science engineer with over a decade of experience in software development He completed his studies at the University of Alicante Spain in 2007 and moved to London in 2010 He has been using Python since 2012 and currently works as a senior software developer and team lead at Sohonet developing real time collaboration applications for the media industry He is also a certified ScrumMaster and was one of the technical reviewers of the first edition of this book I would like to thank my parents for their love good advice and continuous support I would also like to thank all the friends I have met along the way who enriched my life for keeping up