What’s the hardest part of Python to understand?
For nearly 20 years, I’ve been teaching Python to engineers at companies around the world. And if I had to say what most confuses my students, it’s list comprehensions.
And yes, if you’re wondering, set and dict comprehensions are equally confusing.
Comprehensions are both powerful and compact. The syntax, however, is far from obvious. Moreover, it’s not always clear just when or why you should use comprehensions, and when you should instead use a regular “for” loop.
Experienced Python developers know that there is a difference between comprehensions and “for” loops, even if it isn’t obvious to newcomers. Those experts also know that comprehensions are an essential part of a Python developer’s toolbox. It’s a rare day on which I won’t use a comprehension in my Python programming.
Among other things, comprehensions can:
- help you to convert sequences from one type to another
- make it easy to extract information from logfiles
- rearrange data inside of complex data structures
- create lists, sets, and dicts from files
So, how can we help newcomers, who see comprehensions as some combination of weird, unnecessary, and hard to understand? If you know me, then you already know the answer: Clear explanations, followed by lots of practice.
I’m thus delighted to announce the launch of “Comprehending comprehensions,” an online course that teaches Python developers how and why to use comprehensions.
This is an Internet version of a class which I have taught more than 100 times at companies around the world. Through nearly two hours of video and more than 15 exercises, you’ll learn how, when, and why to write and use comprehensions.
If you’re familiar with Python’s basic data types (strings, lists, tuples, dicts, and sets), reading from files and writing simple functions, but don’t yet feel comfortable using comprehensions, then this course is for you: You’ll come out of the course knowing how to write faster, cleaner, and more robust Python code. You’ll know how to handle common situations with data structures and files. And you’ll be better prepared to read and debug code written by others.
In addition to the videos and exercises, this course comes with the slides I use at my in-person training, and the input files you’ll need to solve the exercises.
My goal, as always, is to make you a more fluent Python programmer. If you take this course, you will have made a major step forward on that journey.
As always, I offer discounts to students, pensioners, and people living outside of the 30 wealthiest countries in the world — just e-mail me to request an appropriate coupon code. There are also group discounts, if you want to buy five or more copies for your organization.
Click here to sign up for “Comprehending Comprehensions”!
Questions? Comments? Just leave a comment on this blog or send me e-mail; I’ll respond with an answer right away.