Preface

It is our great pleasure to introduce you to the fourth edition of our book. The first one came out in 2015, and since then the book has been a top seller all around the world.

Ten years ago, being a programmer meant working with certain tools, implementing certain paradigms. Today, the landscape is different. Developers tend to be even more specialized than before, and there is great focus on things like APIs, and distributed applications. We have tried to capture the current trends, and to offer you the best foundational layer we could think of, drawing from our experience as developers who work in a fast-paced industry.

Each new edition has brought about some kind of change. Obsolete chapters were removed, new ones were added, and others again have been amended to reflect the modern ways in which software is written.

This edition features three new chapters. The first one discusses the topic of type hinting. Type hinting is not new to Python, but now we feel it has become such an established practice that the book wouldn’t have been complete without it.

The second one, which discusses the topic of CLI applications, steps in by replacing an old chapter that was about GUIs. Most of what we do with a computer today happens in a browser, and many desktop applications have been built, or rewritten, by leveraging browser components, so we felt that a whole chapter dedicated to GUIs was perhaps a bit obsolete.

Finally, the third one explores the topic of competitive programming.

The remaining chapters have been updated to reflect the latest additions to the language, and improved to make the presentation even simpler and more fluid, while still aiming at offering interesting examples to the reader.

The soul of the book, its essence, is still intact. It shouldn’t feel like yet another Python book. It is, first and foremost, about programming. It tries to convey as much information as possible and, sometimes, when the page count couldn’t allow it, it points to the resources you need to further your knowledge.

It is designed to last. It explains concepts and information in a way that should stand the test of time, for as long as possible. There is great amount of work, thinking, and meetings, that goes into making sure of that.

It is also radically different than its first edition. It is much more mature, more professional, and focuses more on the language and slightly less on projects. We think the line that strikes the balance between these two parts has been drawn in the right place.

It will require you to focus and work hard. All the code is available for download. You can clone the repository from GitHub, if you like. Please check it out. It will help you cement what you will learn when reading these pages. Code is not a static thing. It is very much alive. It changes, it morphs. You will learn much more if you take the time to explore it, change it, and break it. We have left several guidelines in the book, to help you do that.

In closing, I want to express my gratitude to my co-author, Heinrich.

This book is now as much his as it is mine. Every chapter is infused with his talent, his creativity, and the depth of his knowledge. He is also gifted with tremendous memory: he can spot a redundant piece of information in chapters that are 200 pages apart. I can’t do that.

Like me, he has spent many long nights and weekends making sure everything was presented in the best possible way. It is because I have shared this journey with him, that I have so much confidence in the quality of this work.

Our advice for you is to study these pages well, and experiment with the source code. Once you are confident in your Python skills, please don’t stop learning. Try to go beyond the language, transcend it. A senior developer should know certain concepts and master certain skills that cannot be contained within one language, it’s just not possible. Studying other languages helps to learn how to discriminate between those features that pertain to a certain language, and others that are instead more generic, related to programming. Hopefully this book will help you get there.

Enjoy the journey and, whatever you learn, please share it with others.

Fabrizio