This is a simple explanation of the asyncio module and new supporting language features in Python 3.5. Even though the new keywords async and await are new language constructs, they are mostly¹ useless without an event loop, and that is supplied in the standard library as asyncio. Also, you need awaitable functions, which are only supplied by asyncio (or in the growing set of async libraries, like asyncssh, quamash etc.).

[Read More]

This is a simple example to show how Asyncio works without using Asyncio itself, instead using a basic and poorly written event loop. This is only meant to give a flavor of what Asyncio does behind the curtains. I’m avoiding most details of the library design, like callbacks, just to keep this simple. Since this is written as an illustration, rather than real code, I’m going to dispense with trying to keep it 2.7 compatible.

[Read More]

Slots seem to be poorly documented. What they do is simple, but whether they are used is tricky. This is a little mini-post on slots.

[Read More]

This is a quick tutorial over the basics of what metaclasses do.

The Metaclass

Metaclasses, while seemingly a complex topic, really just do something very simple. They control what happens when you have code that turns into a class object. The normal place they are executed is right after the class statement. Let’s see that in action by using print as our metaclass.

[Read More]

I haven’t seen a great deal of practical documentation about using classmethods as factories in Python (which is arguably the most important use of a classmethod, IMO). This post hopes to fill in that gap.

[Read More]

I recently decided to try my hand at making an auto-load extension for Python and Plumbum. I was planning to suggest it as a new feature, then I thought it might be an experimental feature, and now it’s just a blog post. But it was an interesting idea and didn’t seem to be well documented process on the web. So, here it is. The plan was to make commands like this: [Read More]