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)
Other Books You May Enjoy

Removing from dictionaries – the pop() method and the del statement

A common use case for a dictionary is as an associative store: we can keep an association between key and value objects. This means that we may be doing any of the CRUD operations on an item in the dictionary:

  • Create a new key and value pair
  • Retrieve the value associated with a key
  • Update the value associated with a key
  • Delete the key (and the corresponding value) from the dictionary

We have two common variations on this theme:

  • We have the in-memory dictionary, dict, and the variations on this theme in the collections module. The collection only exists while our program is running.
  • We also have persistent storage in the shelve and dbm modules. The data collection is a persistent file in the filesystem, with a dict-like mapping interface.

These are similar, while the distinctions between a shelf.Shelf and dict object are minor. This allows us to...