David Beazley and Brian K. Jones - Python Cookbook

Since 2008, the Python world has been watching the slow evolution ofPython 3. It was always known that the adoption of Python 3 wouldlikely take a long time. In fact, even at the time of thiswriting (2013), most working Python programmers continue to use Python2 in production. A lot has been made about the fact that Python 3 isnot backward compatible with past versions. To be sure, backwardcompatibility is an issue for anyone with an existing code base. However,if you shift your view toward the future, youll find thatPython 3 offers much more than meets the eye.

Just as Python 3 is about the future, this edition of the PythonCookbook represents a major change over past editions. First andforemost, this is meant to be a very forward looking book. All of therecipes have been written and tested with Python 3.3 without regard topast Python versions or the old way of doing things. In fact, many of the recipes will only work with Python 3.3 and above. Doing so maybe a calculated risk, but the ultimate goal is to write a book ofrecipes based on the most modern tools and idioms possible. It ishoped that the recipes can serve as a guide for people writingnew code in Python 3 or those who hope to modernize existing code.

Needless to say, writing a book of recipes in this style presents a certain editorial challenge. An online search for Python recipes returns literally thousands of useful recipes on sites such as ActiveStates Python recipes or Stack Overflow. However, most of these recipes are steeped in history and the past. Besides being written almost exclusively for Python 2, they often contain workarounds and hacks related to differences between old versions of Python (e.g., version 2.3 versus 2.4). Moreover, they often use outdated techniques that have simply become a built-in feature of Python 3.3. Finding recipes exclusively focused on Python 3 can be a bit more difficult.

Rather than attempting to seek out Python 3-specific recipes, thetopics of this book are merely inspired by existing code andtechniques. Using these ideas as a springboard, the writing is anoriginal work that has been deliberately written with the most modernPython programming techniques possible. Thus, it can serve as a referencefor anyone who wants to write their code in a modern style.

In choosing which recipes to include, there is a certain realizationthat it is simply impossible to write a book that covers everypossible thing that someone might do with Python. Thus, a priorityhas been given to topics that focus on the core Python language aswell as tasks that are common to a wide variety of applicationdomains. In addition, many of the recipes aim to illustrate featuresthat are new to Python 3 and more likely to be unknown to evenexperienced programmers using older versions. There is also a certainpreference to recipes that illustrate a generally applicableprogramming technique (i.e., programming patterns) as opposed to thosethat narrowly try to address a very specific practical problem.Although certain third-party packages get coverage, a majority of therecipes focus on the core language and standard library.