Automate the Boring Stuff with Python: Practical Programming for Total Beginners

Python will do the date arithmetic to figure out that 1,000 days after February 27, 2015, will be November 23, 2017. This is useful because when you calculate 1,000 days from a given date, you have to remember how many days are in each month and factor in leap years and other tricky details. The datetime module handles all of this for you.

The pprint.pformat() function produces a string that itself is formatted as valid Python code. By outputting it to a text file named census2010.py, you’ve generated a Python program from your Python program! This may seem complicated, but the advantage is that you can now import census2010.py just like any other Python module.