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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Using argparse to get command-line input

For some applications, it can be better to get the user input from the OS command line without a lot of human interaction. We'd prefer to parse the command-line argument values and either perform the processing or report an error.

For example, at the OS level, we might want to run a program like this:

% python3 -r KM 36.12,-86.67 33.94,-118.40
From (36.12, -86.67) to (33.94, -118.4) in KM = 2887.35

The OS prompt is %. We entered a command of python3 This command had an optional argument, -r KM, and two positional arguments of 36.12,-86.67 and 33.94,-118.40.

The program parses the command-line arguments and writes the result back to the console. This allows a very simple kind of user interaction. It keeps the program very simple. It allows the user to write a shell script to invoke the program or merge the program with other Python programs to create a higher-level program.

If the...