Book Image

Modern Python Standard Library Cookbook

By : Alessandro Molina
Book Image

Modern Python Standard Library Cookbook

By: Alessandro Molina

Overview of this book

The Python 3 Standard Library is a vast array of modules that you can use for developing various kinds of applications. It contains an exhaustive list of libraries, and this book will help you choose the best one to address specific programming problems in Python. The Modern Python Standard Library Cookbook begins with recipes on containers and data structures and guides you in performing effective text management in Python. You will find Python recipes for command-line operations, networking, filesystems and directories, and concurrent execution. You will learn about Python security essentials in Python and get to grips with various development tools for debugging, benchmarking, inspection, error reporting, and tracing. The book includes recipes to help you create graphical user interfaces for your application. You will learn to work with multimedia components and perform mathematical operations on date and time. The recipes will also show you how to deploy different searching and sorting algorithms on your data. By the end of the book, you will have acquired the skills needed to write clean code in Python and develop applications that meet your needs.
Table of Contents (21 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

Weekdays


Building a date for the 20th of the month or for the 3rd week of the month is pretty straightforward, but what if you have to build the date for the 3rd Monday of the month?

How to do it...

Go through these steps:

  1. To approach this problem, we are going to actually generate all the month days that match the requested weekday:
import datetime

def monthweekdays(month, weekday):
    now = datetime.datetime.utcnow()
    d = now.replace(day=1, month=month, hour=0, minute=0, second=0, 
                    microsecond=0)
    days = []
    while d.month == month:
        if d.isoweekday() == weekday:
            days.append(d)
        d += datetime.timedelta(days=1)
    return days
  1. Then, once we have a list of those, grabbing the nth day is just a matter of indexing the resulting list. For example, to grab the Mondays from March:
>>> monthweekdays(3, 1)
[datetime.datetime(2018, 3, 5, 0, 0), 
 datetime.datetime(2018, 3, 12, 0, 0), 
 datetime.datetime(2018, 3, 19, 0, 0), 
 datetime.datetime...