Chapter 2. A Crash Course in Python

People are still crazy about Python after twenty-five years, which I find hard to believe.

Michael Palin

All new employees at DataSciencester are required to go through new employee orientation, the most interesting part of which is a crash course in Python.

This is not a comprehensive Python tutorial but instead is intended to highlight the parts of the language that will be most important to us (some of which are often not the focus of Python tutorials). If you have never used Python before, you probably want to supplement this with some sort of beginner tutorial.

The Zen of Python

Python has a somewhat Zen description of its design principles, which you can also find inside the Python interpreter itself by typing “import this.”

One of the most discussed of these is:

There should be one—and preferably only one—obvious way to do it.

Code written in accordance with this “obvious” way (which may not be obvious at all to a newcomer) is often described as “Pythonic.” Although this is not a book about Python, we will occasionally contrast Pythonic and non-Pythonic ways of accomplishing the same things, and we will generally favor Pythonic solutions to our problems.

Several others touch on aesthetics:

Beautiful is better than ugly. Explicit is better than implicit. Simple is better than complex.

and represent ideals that we will strive for in our code.

Getting Python


As instructions about how to install things can change, while printed ...

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