Suspending the computer using Kupfer

I have recently started using Kupfer again as my application launcher in Ubuntu MATE, and I found it lacked the ability to suspend the computer.

Here is the plugin I wrote to support this.

To install it, quit Kupfer, create a directory in your home dir called .local/share/kupfer/plugins, and create this file inside:

__kupfer_name__ = _("Power management")
__kupfer_sources__ = ("PowerManagementItemsSource", )
__description__ = _("Actions to suspend the computer")
__version__ = "2021-05-05"
__author__ = "Andy Balaam "

from kupfer.plugin import session_support as support

class Suspend (support.CommandLeaf):
    def __init__(self, commands):
        support.CommandLeaf.__init__(self, commands, "Suspend")
    def get_description(self):
        return _("Suspend the computer")
    def get_icon_name(self):
        return "system-suspend"

class PowerManagementItemsSource (support.CommonSource):
	def __init__(self):
		support.CommonSource.__init__(self, _("Power management"))
	def get_items(self):
		return (Suspend((["systemctl", "suspend"],)),)

# Copyright 2021 Andy Balaam, released under the MIT license.

Now restart Kupfer, go to Preferences, Plugins, and tick “Power management”.

You should now see a “Suspend” item if you search for it in the Kupfer interface.

Inspired by: Mate Session Management – Kupfer Plugin.

Reference docs: Kupfer Plugin API

Toggle window decorations on Linux GTK3 with Python3

The Internet is full of outdated Python code for doing things with windows, so here is what I got working today in a Python 3, GTK 3 environment.

This script toggles the window decorations on the active window on and off. I have it bound to Ctrl+NumPadMinus for easy access.

#!/usr/bin/env python3

import gi
gi.require_version('Gdk', '3.0')
gi.require_version('GdkX11', '3.0')
gi.require_version('Wnck', '3.0')
from gi.repository import Gdk
from gi.repository import GdkX11
from gi.repository import Wnck

def active_window(screen):
    for window in screen.get_windows():
       if window.is_active() == True:
            return window

def toggle_decorations(w):
    if w.get_decorations().decorations == 0:

screen = Wnck.Screen.get_default()
display = GdkX11.X11Display.get_default()
window = active_window(screen)
window_id = window.get_xid()

w = GdkX11.X11Window.foreign_new_for_display(display, window_id)

window = None
screen = None

Python Async basics video (100 million HTTP requests)

I found something difficult in Python, which was a bit of a first, so I wrote a whole blog series about it, and now a whole video:

Slides: Python Async Basics slides

Blog posts: asyncio basics, large numbers in parallel, parallel HTTP requests, adding to stdlib

London Python Meetup January 2019 – Async Python and GeoPandas

It was a pleasure to go to the London Python Meetup organised by @python_london. There were plenty of friendly people and interesting conversations.

I gave a talk “Making 100 million requests with Python aiohttp” (slides, Blog post) explaining the basics of writing async code in Python 3 and how I used that to make a very large number of HTTP requests.

Andy giving the presentation

(Photo by CB Bailey.)

Hopefully it was helpful – there were several good questions, so I am optimistic that people were engaged with it.

After that, there was an excellent talk by Gareth Lloyd called “GeoPandas, the geospatial extension for Pandas” in which he explained how to use the very well-developed geo-spatial data tools available in the Python ecosphere to transform, combine, plot and analyse data which includes location information. I was really impressed with how easy the libraries looked to use, and also with the cool Jupyter notebook Gareth used to explain the ideas using live demos.

London Python Meetups seem like a cool place to meet Pythonistas of all levels of experience in a nice, low-pressure environment!

Meetup link: aiohttp / GeoPandas

Graft Animation Language on Raspberry Pi

Because the Rapsberry Pi uses a slightly older Python version, there is a special version of Graft for it.

Here’s how to get it:

  • Open a terminal window by clicking the black icon with a “>” symbol on it at the top near the left.
  • First we need to install a couple of things Graft needs, so type this, then press Enter:
    sudo apt install python3-attr at-spi2-core
  • If you want to be able to make animated GIFs, install one more thing:
    sudo apt install imagemagick
  • To download Graft and switch to the Raspberry Pi version, type in these commands, pressing Enter after each line.
    git clone
    cd graft
    git checkout raspberry-pi
  • Now, you should be able to run Graft just like on another computer, for example, like this:
    ./graft 'd+=10 S()'
  • If you’re looking for a fun way to start, why not try the worksheet “Tell a story by making animations with code”?

    For more info, see Graft Raspberry Pi Setup.