python

Ansible runs on Python, and Python runs on... well pretty much everything. Including newer RISC-V machines.

But Ansible has a lot of dependencies, and some of these dependencies have caused frustration from time to time on x86 and Arm (so having issues with a dependency is just a way of life when you enter dependency hell)... but in this case, for the past few months, I've never had luck installing Ansible from PyPI (Python's Package Index) on any RISC-V system, using pip install ansible.

I prefer installing this way (rather than compiling from source or from system packages) because it generally gets the latest version of Ansible, with an easy upgrade/downgrade path. It's also easy to add ansible to a Python requirements.txt file and install it alongside other package dependencies.

Regardless, the cryptography library, which requires a Rust compiler to build if the package is not already built for a particular system, has made it difficult to install Ansible from pip:

Red Hat Enterprise Linux 8 is supported until 2029, and that distribution includes Python 3.6 for system python. Ansible's long been stuck between a rock and a hard place supporting certain modules (especially packaging modules like dnf/yum on RHEL and its derivatives, because the Python bindings for the packaging modules are stuck supporting system Python.

Users are getting errors like:

/bin/sh: /usr/bin/python3: No such file or directory
The module failed to execute correctly, you probably need to set the interpreter.\nSee stdout/stderr for the exact error.

...or...

SyntaxError: future feature annotations is not defined

As ansible-core evolves, they don't want to support old insecure versions of Python forever—Python 3.6 was out of security support back in 2021!.

I recently tried setting up an M.2 Coral TPU on a machine running Debian 12 'Bookworm', which ships with Python 3.11, making the installation of the pyCoral library very difficult (maybe impossible for now?).

Some of the devs responded 'just install an older Ubuntu or Debian release' in the GitHub issues, as that would give me a compatible Python version (3.9 or earlier)... but in this case I didn't want to do that.

On new Debian 12 Bookworm and Ubuntu 24.04 Noble Numbat installs, when I try running pip3 install [something] (whether that's Ansible or some other Python tool), I get the following error message:

Today I needed to play back an MP3 or WAV file through a USB audio device on a Raspberry Pi, in a Python script. "Should be easy!" I thought!

Well, a couple hours later I decided to write this blog post to document the easiest way to do it, since I had to take quite a journey to get to the point where sound actually plays through the USB audio output.

The problem is most guides, like this simple one from Raspberry Pi's project site, assume two things:

I've started getting a lot of bug reports on my repos to the effect of "Ansible won't install on my Raspberry Pi anymore". Accompanying it is a debug message like one of the following:

$ python3 -m pip install ansible
...
No matching distribution found for ansible-core<2.13,>=2.12.0 (from ansible)

# Alternatively:
ERROR: No matching distribution found for ansible-core<2.13,>=2.12.0

The problem is ansible-core 2.12 has a new hard requirement for Python 3.8 or newer. And ansible-core 2.12 is included in Ansible 5.0.0, which was recently released. Raspberry Pi OS, which was based on Debian 10 ("Buster") until recently, includes Python 3.7, which is too old to satisfy Ansible's installation requirements.

There was recently a fix that makes it so Ansible 5.x won't get installed on these older systems, but who wants to get stuck on old unsupported Ansible versions?

There are three options:

In the class of 'out there' projects, I recently added a little AI to my leaf blower:

The short of it: I have a face detection algorithm running which, when a certain individual enters the field of the Pi's vision, triggers a servo that powers on the blower, releasing a powerful air blast.

I've been wanting to play around with face detection on the Pi for some time, but the Pi Zero I use in most of my camera projects is seriously underpowered for this kind of work.

CM4Ext Nano

So when Harlab (Hardware Laboratory) told me they'd like to send me a CM4Ext Nano board for testing, I thought it'd be the perfect opportunity to play with machine vision on the Pi.

Harbinger of the Internet of Dings

Last year, I built the first version of what I call the "Raspberry Pi Bell Slapper." It was named that because it used a servo and a metal arm to slap the top of the bell in response to a stimuli—in this case, an email from a donation notification system for a local non-profit radio station.

This year, that same radio station had another one of their fund-raisers (a radiothon), and to celebrate, I thought I'd do the thing justice, with a better circuit (using a solenoid instead of a servo) and a 3D printed enclosure. And this is the result:

There is a Raspberry Pi Zero W with a custom solenoid control HAT on top inside the case to the left, and the solenoid right up against the bell, which is mounted on the right.

I also posted a video on YouTube exploring the project in detail: The Raspberry Pi IoT Notification Bell.

Recently I upgraded from an Intel-based MacBook Pro to two M1 Macs. As part of the upgrade, I also made sure to refine my Mac setup automation with Ansible and my Mac Development Ansible Playbook.

But one weird thing I noticed was no matter how I installed Ansible on my new Macs, I couldn't get libyaml support to work:

Ubuntu 16.04 and 18.04 (and likely future versions) often don't have Python 2 installed by default. Sometimes Python 3 is installed, available at /usr/bin/python3, but for many minimal images I've used, there's no preinstalled Python at all.

Therefore, when you run Ansible playbooks against new VMs running Ubuntu, you might be greeted with the following error: