Book Image

Modern Python Cookbook - Second Edition

By : Steven F. Lott
Book Image

Modern Python Cookbook - Second Edition

By: Steven F. Lott

Overview of this book

Python is the preferred choice of developers, engineers, data scientists, and hobbyists everywhere. It is a great language that can power your applications and provide great speed, safety, and scalability. It can be used for simple scripting or sophisticated web applications. By exposing Python as a series of simple recipes, this book gives you insight into specific language features in a particular context. Having a tangible context helps make the language or a given standard library feature easier to understand. This book comes with 133 recipes on the latest version of Python 3.8. The recipes will benefit everyone, from beginners just starting out with Python to experts. You'll not only learn Python programming concepts but also how to build complex applications. The recipes will touch upon all necessary Python concepts related to data structures, object oriented programming, functional programming, and statistical programming. You will get acquainted with the nuances of Python syntax and how to effectively take advantage of it. By the end of this Python book, you will be equipped with knowledge of testing, web services, configuration, and application integration tips and tricks. You will be armed with the knowledge of how to create applications with flexible logging, powerful configuration, command-line options, automated unit tests, and good documentation.
Table of Contents (18 chapters)
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Managing a context using the with statement

There are many instances where our scripts will be entangled with external resources. The most common examples are disk files and network connections to external hosts. A common bug is retaining these entanglements forever, tying up these resources uselessly. These are sometimes called memory leaks because the available memory is reduced each time a new file is opened without closing a previously used file.

We'd like to isolate each entanglement so that we can be sure that the resource is acquired and released properly. The idea is to create a context in which our script uses an external resource. At the end of the context, our program is no longer bound to the resource and we want to be guaranteed that the resource is released.

Getting ready

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