(Thanks to Brian for his feedback. All mistakes and omissions that remain are mine.)

Some commands have a --dry-run option, which simulates running the command but without taking effect. Sometimes the option exists for speed reasons: just pretending to do something is faster than doing it. However, more often this …

(Thanks to Mark Rice for his helpful suggestions. Any mistakes or omissions that remain are my responsibility.)

Some Python projects are designed to be libraries, consumed by other projects. These are most of the things people consider "Python projects": for example, Twisted, Flask, and most other open source tools. However …

(Thanks to Avy Faingezicht and Donald Stufft for giving me encouragement and feedback. All mistakes that remain are mine.)

"eyes have they, but they see not" -- Psalms, 135:16

Eyes are expensive to maintain. They require protection from the elements, constant lubrication, behavioral adaptations to protect them and more. However …

When I was in my early 20s, I was OK at programming, but I definitely didn't like it. Then, one evening, I read the Python tutorial. That evening changed my mind. I woke up the next morning, like Neo in the matrix, and knew Python.

I was doing statistics at …

A common way to expose an API in Python is as inheritance. Though many projects do that, there is a better way.

But first, let's see. How popular is inheritance-as-an-API, anyway?

Let's go to the Twisted website. Right at the center of the screen, at prime real-estate, we see:

What's …

Assume MyClass._dangerous(self) is a private method. We could have implemented the same functionality without a private method as follows:

• Define a class InnerClass with the same __init__ as MyClass
• Define InnerClass.dangerous(self) with the same logic of MyClass._dangerous
• Make MyClass into a wrapper class over InnerClass …

We would like Twisted to support contextvars -- this would allow cross-async libraries, like eliot to do fancy things.

Klein is almost ready to be used as-is. Glyph has the good branch which adds

• CSRF protection
• Forms
• Sessions
• Authentication

But it is too big, and we need to break it to …

We started out the conversation with talking about writing good Dockerfiles. There is no list of "best practices" yet. Hynek reiterated for us "ship applications, not build environments". Moshe summarized it as "don't put gcc in the deployed image."

We discussed a little bit what we are trying to achieve …

Announcment: My book, from python import better, has been published. This post is based on one of the chapters from it.

When Python started out, one of the oft-touted benefits was "batteries included!". Gone were the days of searching for which XML parsing library was the best -- just use the …

(Thanks to Glyph Lefkowitz for some of the inspiration for this port, and to Mahmoud Hashemi for helpful comments and suggestions. All mistakes and issues that remain are mine alone.)

The Python REPL has always been touted as one of Python's greatest strengths. With Jupyter, Jupyter Lab in its latest …