Reuven Lerner: Announcing: Python standard library, video explainer

A month or two ago, I saw an online quiz that caught my eye: How much of the Python standard library do you know?

Now, the “standard library” is the collection of modules and packages that come with Python. It constitutes the “batteries” that “batteries included” refers to in the Python world. And the standard library is big, with about 300 modules, each of which contains functions, classes, and values.  Knowing the standard library, and how to use it, is essential to productive use of Python.

And yet, a large number of the people responding indicated that they knew very little of the standard library.  Which makes sense, given that each of us tends to focus on what’s important to our jobs.

Indeed, I’ve been using Python for a long time.  And I had to admit that there are large parts of the standard library with which I’m totally unfamiliar.  I’m sure that there are gems (no Ruby pun intended) in there that I could make use of in my work, if I only knew about them.


I’ve thus decided to try an experiment, namely to walk through the entire standard library (or as much as I can physically, humanly do) in an open-ended YouTube video series.  I’ve already uploaded a number of the videos, and I will be uploading a few new ones every week.  I’m starting with the builtin types, walking through each of their methods — but I’ll then proceed to the other and lesser-known modules.

This is all new content, certainly overlapping my previous writing and courses to some degree, but made new for this series.  It’s less formal than my courses, without any exercises or background theory connecting it all together.  And yet, I’ve already learned about a number of methods and techniques — and I assume that the same will be true for you.

This video explainer is on YouTube, so you can watch it easily by subscribing to my channel there, at  This is a long-term project, but one that I hope will be helpful and of use to you and to the entire Python community!  Subscribe to my channel, and you’ll get updated whenever I add new videos.

The post Announcing: Python standard library, video explainer appeared first on Reuven Lerner.

Planet Python

Data School: Data science best practices with pandas (video tutorial)

Data science best practices with pandas (video tutorial)

The pandas library is a powerful tool for multiple phases of the data science workflow, including data cleaning, visualization, and exploratory data analysis. However, the size and complexity of the pandas library makes it challenging to discover the best way to accomplish any given task.

In this in-depth tutorial, which I presented at PyCon 2019, you’ll use pandas to answer questions about a real-world dataset. Through each exercise, you’ll learn important data science skills as well as "best practices" for using pandas. By the end of the tutorial, you’ll be more fluent at using pandas to correctly and efficiently answer your own data science questions.

This is an intermediate level tutorial, so if you’re new to pandas, I recommend starting with my other video series: Easier data analysis with pandas.

If you want to follow along with the exercises at home, you can download the dataset and notebook from GitHub.

Here are some of the topics covered in the video:

  • adjusting for bias in your dataset
  • handling missing values
  • choosing an appropriate plot
  • customizing your plot
  • using the datetime data type
  • filtering using loc versus query
  • using multiple aggregation functions
  • checking for small sample sizes
  • method chaining
  • verifying your results using random samples
  • evaluating a "stringifed" Python container
  • applying a custom function to a Series
  • writing lambda functions

Let me know if you have any questions, and I’m happy to answer them!

P.S. If you like this video, you should check out my interactive pandas course, Analyzing Police Activity with pandas.

Planet Python

MacADUK 2019 Presentation Video online

The recording of my MacADUK 2019 presentation: “Modern Deployment Workflows for Business” is online and available:

You can find this video and the other recorded presentations in the MacADUK 2019 playlist on YouTube.

I am really happy with how this presentation turned out and I could be more happy with the keyframe that was chosen for the video.

You can find the notes and slides at the session’s permanent page.

Many thanks again to all those who put a lot of effort into making MacADUK 2019 the great conference it was. Also thanks to the attendees with all their great feedback and applause. See you all again next year!

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