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How to program hotstrings in python like in autohotkey

I want to make hotstrings in python that converts one word when typed into another after some processing, since AHK is very limiting when it comes to determining which word to type. Right now, I am using a hotstring in ahk that runs code on the command line that runs a python script with the word that I typed as arguments. Then I use pyautogui to type the word. However, this is very slow and does not work when typing at speed. I'm looking for a way to do this all with python and without ahk, but I have not found a way to do hotstrings in python. For example, every time I type the word "test" it replaces it with "testing." Thanks for your help. I'm running the latest version of Python and Windows 10 if that is useful to anyone by the way.

(if you want to process it as each letter is typed(t,te,tes,test), you should edit your question)
I call my SymPy functions using ahk hotkeys. I register the python script as a COM server and load it using ahk.
I do not notice any latency.
you'll need pywin32, but don't download using pip install pywin32
download from https://github.com/mhammond/pywin32/releases
OR ELSE IT WON'T WORK for AutoHotkeyU64.exe, it will only work for AutoHotkeyU32.exe.
make sure to download amd64, (I downloaded pywin32-300.win-amd64-py3.8.exe)
here's why: how to register a 64bit python COM server
toUppercase COM server.py
class BasicServer:
# list of all method names exposed to COM
_public_methods_ = ["toUppercase"]
#staticmethod
def toUppercase(string):
return string.upper()
if __name__ == "__main__":
import sys
if len(sys.argv) < 2:
print("Error: need to supply arg (""--register"" or ""--unregister"")")
sys.exit(1)
else:
import win32com.server.register
import win32com.server.exception
# this server's CLSID
# NEVER copy the following ID
# Use "print(pythoncom.CreateGuid())" to make a new one.
myClsid="{C70F3BF7-2947-4F87-B31E-9F5B8B13D24F}"
# this server's (user-friendly) program ID
myProgID="Python.stringUppercaser"
import ctypes
def make_sure_is_admin():
try:
if ctypes.windll.shell32.IsUserAnAdmin():
return
except:
pass
exit("YOU MUST RUN THIS AS ADMIN")
if sys.argv[1] == "--register":
make_sure_is_admin()
import pythoncom
import os.path
realPath = os.path.realpath(__file__)
dirName = os.path.dirname(realPath)
nameOfThisFile = os.path.basename(realPath)
nameNoExt = os.path.splitext(nameOfThisFile)[0]
# stuff will be written here
# HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\${myClsid}
# HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C70F3BF7-2947-4F87-B31E-9F5B8B13D24F}
# and here
# HKEY_LOCAL_MACHINE\SOFTWARE\Classes\${myProgID}
# HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Python.stringUppercaser
win32com.server.register.RegisterServer(
clsid=myClsid,
# I guess this is {fileNameNoExt}.{className}
pythonInstString=nameNoExt + ".BasicServer", #toUppercase COM server.BasicServer
progID=myProgID,
# optional description
desc="return uppercased string",
#we only want the registry key LocalServer32
#we DO NOT WANT InProcServer32: pythoncom39.dll, NO NO NO
clsctx=pythoncom.CLSCTX_LOCAL_SERVER,
#this is needed if this file isn't in PYTHONPATH: it tells regedit which directory this file is located
#this will write HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{C70F3BF7-2947-4F87-B31E-9F5B8B13D24F}\PythonCOMPath : dirName
addnPath=dirName,
)
print("Registered COM server.")
# don't use UseCommandLine(), as it will write InProcServer32: pythoncom39.dll
# win32com.server.register.UseCommandLine(BasicServer)
elif sys.argv[1] == "--unregister":
make_sure_is_admin()
print("Starting to unregister...")
win32com.server.register.UnregisterServer(myClsid, myProgID)
print("Unregistered COM server.")
else:
print("Error: arg not recognized")
you first need to register the python COM server:
first, get your own CLSID: just use a python shell.
import pythoncom
print(pythoncom.CreateGuid())
then, set myClsid to that output
to register:
python "toUppercase COM server.py" --register
to unregister:
python "toUppercase COM server.py" --unregister
hotstring python toUppercase.ahk
#NoEnv ; Recommended for performance and compatibility with future AutoHotkey releases.
#SingleInstance, force
SendMode Input ; Recommended for new scripts due to its superior speed and reliability.
SetWorkingDir %A_ScriptDir% ; Ensures a consistent starting directory.
SetBatchLines, -1
#KeyHistory 0
ListLines Off
#Persistent
#MaxThreadsPerHotkey 4
pythonComServer:=ComObjCreate("Python.stringUppercaser")
; OR
; pythonComServer:=ComObjCreate("{C70F3BF7-2947-4F87-B31E-9F5B8B13D24F}") ;use your own CLSID
; * do not wait for string to end
; C case sensitive
:*:hello world::
savedHotstring:=A_ThisHotkey
;theActualHotstring=savedHotstring[second colon:end of string]
theActualHotstring:=SubStr(savedHotstring, InStr(savedHotstring, ":",, 2) + 1)
send, % pythonComServer.toUppercase(theActualHotstring)
return
f3::Exitapp
you can test the speed of hotstring hello world, it's very fast for me.
Edit def toUppercase(string): to your liking

Custom Ansible module is giving param extra params error

I am trying to implement hostname like module and my target machine in an amazon-ec2. But When I am running the script its giving me below error:
[ansible-user#ansible-master ~]$ ansible node1 -m edit_hostname.py -a node2
ERROR! this task 'edit_hostname.py' has extra params, which is only allowed in the following modules: meta, group_by, add_host, include_tasks, import_role, raw, set_fact, command, win_shell, import_tasks, script, shell, include_vars, include_role, include, win_command
My module is like this:
#!/usr/bin/python
from ansible.module_utils.basic import *
try:
import json
except ImportError:
import simplejson as json
def write_to_file(module, hostname, hostname_file):
try:
with open(hostname_file, 'w+') as f:
try:
f.write("%s\n" %hostname)
finally:
f.close()
except Exception:
err = get_exception()
module.fail_json(msg="failed to write to the /etc/hostname file")
def main():
hostname_file = '/etc/hostname'
module = AnsibleModule(argument_spec=dict(name=dict(required=True, type=str)))
name = module.params['name']
write_to _file(module, name, hostname_file)
module.exit_json(changed=True, meta=name)
if __name__ == "__main__":
main()
I don't know where I am making the mistake. Any help will be greatly appreciated. Thank you.

When developing a new module, I would recommend to use the boilerplate described in the documentation. This also shows that you'll need to use AnsibleModule to define your arguments.
In your main, you should add something like the following:
def main():
# define available arguments/parameters a user can pass to the module
module_args = dict(
name=dict(type='str', required=True)
)
# seed the result dict in the object
# we primarily care about changed and state
# change is if this module effectively modified the target
# state will include any data that you want your module to pass back
# for consumption, for example, in a subsequent task
result = dict(
changed=False,
original_hostname='',
hostname=''
)
module = AnsibleModule(
argument_spec=module_args
supports_check_mode=False
)
# manipulate or modify the state as needed (this is going to be the
# part where your module will do what it needs to do)
result['original_hostname'] = module.params['name']
result['hostname'] = 'goodbye'
# use whatever logic you need to determine whether or not this module
# made any modifications to your target
result['changed'] = True
# in the event of a successful module execution, you will want to
# simple AnsibleModule.exit_json(), passing the key/value results
module.exit_json(**result)
Then, you can call the module like so:
ansible node1 -m mymodule.py -a "name=myname"

ERROR! this task 'edit_hostname.py' has extra params, which is only allowed in the following modules: meta, group_by, add_host, include_tasks, import_role, raw, set_fact, command, win_shell, import_tasks, script, shell, include_vars, include_role, include, win_command
As explained by your error message, an anonymous default parameter is only supported by a limited number of modules. In your custom module, the paramter you created is called name. Moreover, you should not include the .py extension in the module name. You have to call your module like so as an ad-hoc command:
$ ansible node1 -m edit_hostname -a name=node2
I did not test your module code so you may have further errors to fix.
Meanwhile, I still strongly suggest you use the default boilerplate from the ansible documentation as proposed in #Simon's answer.

Python - bulk promote variables to parent scope

In python 2.7, I want to run:
$ ./script.py initparms.py
This is a trick to supply a parameter file to script.py, since initparms.py contains several python variables e.g.
Ldir = '/home/marzipan/jelly'
LMaps = True
# etc.
script.py contains:
X = __import__(sys.argv[1])
Ldir = X.Ldir
LMaps = X.Lmaps
# etc.
I want to do a bulk promotion of the variables in X so they are available to script.py, without spelling out each one in the code by hand.
Things like
import __import__(sys.argv[1])
or
from sys.argv[1] import *
don't work. Almost there perhaps... Any ideas? Thanks!

here's a one-liner:
globals().update(__import__(sys.argv[1]).__dict__)

You can use execfile:
execfile(sys.argv[1])
Of course, the usual warnings with exec or eval apply (Your script has no way of knowing whether it is running trusted or untrusted code).
My suggestion would be to not do what you're doing and instead use configparser and handling the configuration though there.

You could do something like this:
import os
import imp
import sys
try:
module_name = sys.argv[1]
module_info = imp.find_module(module_name, [os.path.abspath(os.path.dirname(__file__))] + sys.path)
module_properties = imp.load_module(module_name, *module_info)
except ImportError:
pass
else:
try:
attrlist = module_properties.__all__
except AttributeError:
attrlist = dir(module_properties)
for attr in attrlist:
if attr.startswith('__'):
continue
globals()[attr] = getattr(module_properties, attr)
Little complicated, but gets the job done.

Determine Device of Filesystem in Python

How do you use Python to determine which Linux device/partition contains a given filesystem?
e.g.
>>> get_filesystem_device('/')
/dev/sda
>>> get_filesystem_partition('/')
/dev/sda1

Your question was about Linux, so this is (more or less) linux specific.
Below is code example for three variants for mapping major/minor to a device name.
Parse /proc/partitions.
Ask hal. Hal also keeps track of "parent" device, meaning you can easily get the disk aswell as the partition.
Check sysfs yourself. This is where hal gets its information from.
I'd say that /proc/partitions is simplest - it is just one file to open and check. hal gives you most information, and abstracts away lots of details. sysfs may be viewed as more correct that /proc/partitions and doesn't require hal to be running.
For a desktop program I would go for hal. On an embedded system I'd go with sysfs.
import os
def main():
dev = os.stat("/home/").st_dev
major, minor = os.major(dev), os.minor(dev)
print "/proc/partitions says:", ask_proc_partitions(major, minor)
print "HAL says:", ask_hal(major, minor)
print "/sys says:", ask_sysfs(major, minor)
def _parse_proc_partitions():
res = {}
for line in file("/proc/partitions"):
fields = line.split()
try:
tmaj = int(fields[0])
tmin = int(fields[1])
name = fields[3]
res[(tmaj, tmin)] = name
except:
# just ignore parse errors in header/separator lines
pass
return res
def ask_proc_partitions(major, minor):
d = _parse_proc_partitions()
return d[(major, minor)]
def ask_hal(major, minor):
import dbus
bus = dbus.SystemBus()
halobj = bus.get_object('org.freedesktop.Hal', '/org/freedesktop/Hal/Manager')
hal = dbus.Interface(halobj, 'org.freedesktop.Hal.Manager')
def getdevprops(p):
bdevi = dbus.Interface(bus.get_object('org.freedesktop.Hal', p),
"org.freedesktop.Hal.Device")
return bdevi.GetAllProperties()
bdevs = hal.FindDeviceByCapability("block")
for bdev in bdevs:
props = getdevprops(bdev)
if (props['block.major'], props['block.minor']) == (major, minor):
parentprops = getdevprops(props['info.parent'])
return (str(props['block.device']),
str(parentprops['block.device']))
def ask_sysfs(major, minor):
from glob import glob
needle = "%d:%d" % (major, minor)
files = glob("/sys/class/block/*/dev")
for f in files:
if file(f).read().strip() == needle:
return os.path.dirname(f)
return None
if __name__ == '__main__':
main()

It looks like this post has some of your answer (still not sure just how to grab the major/minor out of the /dev/sda2 entry to match it up with what os.stat() returns for /:
Device number in stat command output
>>> import os
>>> print hex(os.stat('/')[2])
0x802
\ \minor device number
\major device number
[me#server /]$ ls -l /dev/sda2
brw-rw---- 1 root disk 8, 2 Jun 24 2004 /dev/sda2
[me#server jgaines2]$ \ \minor device number
\major device number

I recently had a need for this solution also. After seeing all the convoluted methods of getting the result I wanted through pure python, I decided to turn to the shell for help.
import subprocess
device = subprocess.check_output("grep '/filesystem' /proc/mounts | awk '{printf $1}'", shell=True)
print device
This gives me exactly what I want, the device string for where my filesystem is mounted.
Short, sweet, and runs in python. :)

There are problems with quite a few of the above solutions. There's actually a problem with the question as well.
The last answer (searching /proc/mounts) just doesn't work: searching for "/" will match every line in /proc/mounts. Even correcting this like this won't work:
import subprocess
device = subprocess.check_output("awk '$2 == \"/filesystem\" { print $1}' /proc/mounts", shell=True)
print device
When "/filesystem" is "/" you'll typically get two entries, one for "rootfs" and one for the actual device. It also won't work when the mounted file system name has spaces in it (the space appears as \040 in /proc/mounts).
The problem is made worse with btrfs subvolumes. Each subvolume is mounted separately but they all share the same device. If you're trying to use a btrfs snapshot for backups (as I was) then you need the subvolume name and an indication of the filesystem type.
This function returns a tuple of (device, mountpoint, filesystem) and seems to work:
import os
def get_filesystem_partition(fs):
res = None
dev = os.lstat(fs).st_dev
for line in file('/proc/mounts'):
# lines are device, mountpoint, filesystem, <rest>
# later entries override earlier ones
line = [s.decode('string_escape') for s in line.split()[:3]]
if dev == os.lstat(line[1]).st_dev:
res = tuple(line)
return res
That seems to work for all the cases I can think of, although I expect that there are still pathological cases where it falls to bits.

It is not the purdiest, but this will get you started:
#!/usr/bin/python
import os, stat, subprocess, shlex, re, sys
dev=os.stat('/')[stat.ST_DEV]
major=os.major(dev)
minor=os.minor(dev)
out = subprocess.Popen(shlex.split("df /"), stdout=subprocess.PIPE).communicate()
m=re.search(r'(/[^\s]+)\s',str(out))
if m:
mp= m.group(1)
else:
print "cannot parse df"
sys.exit(2)
print "'/' mounted at '%s' with dev number %i, %i" % (mp,major,minor)
On OS X:
'/' mounted at '/dev/disk0s2' with dev number 14, 2
On Ubuntu:
'/' mounted at '/dev/sda1' with dev number 8, 1
To get the device name, chop off the minor number from the partition name. On OS X, also chop the 's' + minor number.

How about using the (linux) blkid command (/sbin/blkid)
$ uname --kernel-name --kernel-release
Linux 3.2.0-4-amd64
$ python --version
Python 2.7.3
-
#!/usr/bin/env python
import subprocess
sys_command = "/sbin/blkid"
proc = subprocess.Popen(sys_command,
stdout=subprocess.PIPE,
shell=True)
# proc.communicate() returns a tuple (stdout,stderr)
blkid_output = proc.communicate()[0]
print blkid_output
Here's the output on a dual-boot laptop with an (unmounted) USB drive (sdb1)
$ ./blkid.py
/dev/sda1: LABEL="RECOVERY" UUID="xxxx-xxxx" TYPE="vfat"
/dev/sda2: LABEL="OS" UUID="xxxxxxxxxxxxxxx" TYPE="ntfs"
/dev/sda5: UUID="xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" TYPE="ext4"
/dev/sda6: UUID="xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" TYPE="swap"
/dev/sda7: UUID="xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" TYPE="ext4"
/dev/sdb1: LABEL="CrunchBang" TYPE="iso9660"

Here is how you can simply get the devices major and minor numbers:
import os
major, minor = divmod(os.stat('/').st_dev, 256)

How can I change my desktop background with python?

How can I change my desktop background with python?
I want to do it in both Windows and Linux.

On Windows with python2.5 or higher, use ctypes to load user32.dll and call SystemParametersInfo() with SPI_SETDESKWALLPAPER action.
For example:
import ctypes
SPI_SETDESKWALLPAPER = 20
ctypes.windll.user32.SystemParametersInfoA(SPI_SETDESKWALLPAPER, 0, "image.jpg" , 0)

For Python3.5, SystemParametersInfoA doesn't work. Use SystemParametersInfoW.
import ctypes
ctypes.windll.user32.SystemParametersInfoW(20, 0, "absolute path" , 0)

I use the following method in one of my initial projects:
def set_wallpaper(self,file_loc, first_run):
# Note: There are two common Linux desktop environments where
# I have not been able to set the desktop background from
# command line: KDE, Enlightenment
desktop_env = self.get_desktop_environment()
try:
if desktop_env in ["gnome", "unity", "cinnamon"]:
uri = "'file://%s'" % file_loc
try:
SCHEMA = "org.gnome.desktop.background"
KEY = "picture-uri"
gsettings = Gio.Settings.new(SCHEMA)
gsettings.set_string(KEY, uri)
except:
args = ["gsettings", "set", "org.gnome.desktop.background", "picture-uri", uri]
subprocess.Popen(args)
elif desktop_env=="mate":
try: # MATE >= 1.6
# info from http://wiki.mate-desktop.org/docs:gsettings
args = ["gsettings", "set", "org.mate.background", "picture-filename", "'%s'" % file_loc]
subprocess.Popen(args)
except: # MATE < 1.6
# From https://bugs.launchpad.net/variety/+bug/1033918
args = ["mateconftool-2","-t","string","--set","/desktop/mate/background/picture_filename",'"%s"' %file_loc]
subprocess.Popen(args)
elif desktop_env=="gnome2": # Not tested
# From https://bugs.launchpad.net/variety/+bug/1033918
args = ["gconftool-2","-t","string","--set","/desktop/gnome/background/picture_filename", '"%s"' %file_loc]
subprocess.Popen(args)
## KDE4 is difficult
## see http://blog.zx2c4.com/699 for a solution that might work
elif desktop_env in ["kde3", "trinity"]:
# From http://ubuntuforums.org/archive/index.php/t-803417.html
args = 'dcop kdesktop KBackgroundIface setWallpaper 0 "%s" 6' % file_loc
subprocess.Popen(args,shell=True)
elif desktop_env=="xfce4":
#From http://www.commandlinefu.com/commands/view/2055/change-wallpaper-for-xfce4-4.6.0
if first_run:
args0 = ["xfconf-query", "-c", "xfce4-desktop", "-p", "/backdrop/screen0/monitor0/image-path", "-s", file_loc]
args1 = ["xfconf-query", "-c", "xfce4-desktop", "-p", "/backdrop/screen0/monitor0/image-style", "-s", "3"]
args2 = ["xfconf-query", "-c", "xfce4-desktop", "-p", "/backdrop/screen0/monitor0/image-show", "-s", "true"]
subprocess.Popen(args0)
subprocess.Popen(args1)
subprocess.Popen(args2)
args = ["xfdesktop","--reload"]
subprocess.Popen(args)
elif desktop_env=="razor-qt": #TODO: implement reload of desktop when possible
if first_run:
desktop_conf = configparser.ConfigParser()
# Development version
desktop_conf_file = os.path.join(self.get_config_dir("razor"),"desktop.conf")
if os.path.isfile(desktop_conf_file):
config_option = r"screens\1\desktops\1\wallpaper"
else:
desktop_conf_file = os.path.join(self.get_home_dir(),".razor/desktop.conf")
config_option = r"desktops\1\wallpaper"
desktop_conf.read(os.path.join(desktop_conf_file))
try:
if desktop_conf.has_option("razor",config_option): #only replacing a value
desktop_conf.set("razor",config_option,file_loc)
with codecs.open(desktop_conf_file, "w", encoding="utf-8", errors="replace") as f:
desktop_conf.write(f)
except:
pass
else:
#TODO: reload desktop when possible
pass
elif desktop_env in ["fluxbox","jwm","openbox","afterstep"]:
#http://fluxbox-wiki.org/index.php/Howto_set_the_background
# used fbsetbg on jwm too since I am too lazy to edit the XML configuration
# now where fbsetbg does the job excellent anyway.
# and I have not figured out how else it can be set on Openbox and AfterSTep
# but fbsetbg works excellent here too.
try:
args = ["fbsetbg", file_loc]
subprocess.Popen(args)
except:
sys.stderr.write("ERROR: Failed to set wallpaper with fbsetbg!\n")
sys.stderr.write("Please make sre that You have fbsetbg installed.\n")
elif desktop_env=="icewm":
# command found at http://urukrama.wordpress.com/2007/12/05/desktop-backgrounds-in-window-managers/
args = ["icewmbg", file_loc]
subprocess.Popen(args)
elif desktop_env=="blackbox":
# command found at http://blackboxwm.sourceforge.net/BlackboxDocumentation/BlackboxBackground
args = ["bsetbg", "-full", file_loc]
subprocess.Popen(args)
elif desktop_env=="lxde":
args = "pcmanfm --set-wallpaper %s --wallpaper-mode=scaled" % file_loc
subprocess.Popen(args,shell=True)
elif desktop_env=="windowmaker":
# From http://www.commandlinefu.com/commands/view/3857/set-wallpaper-on-windowmaker-in-one-line
args = "wmsetbg -s -u %s" % file_loc
subprocess.Popen(args,shell=True)
## NOT TESTED BELOW - don't want to mess things up ##
#elif desktop_env=="enlightenment": # I have not been able to make it work on e17. On e16 it would have been something in this direction
# args = "enlightenment_remote -desktop-bg-add 0 0 0 0 %s" % file_loc
# subprocess.Popen(args,shell=True)
#elif desktop_env=="windows": #Not tested since I do not run this on Windows
# #From https://stackoverflow.com/questions/1977694/change-desktop-background
# import ctypes
# SPI_SETDESKWALLPAPER = 20
# ctypes.windll.user32.SystemParametersInfoA(SPI_SETDESKWALLPAPER, 0, file_loc , 0)
#elif desktop_env=="mac": #Not tested since I do not have a mac
# #From https://stackoverflow.com/questions/431205/how-can-i-programatically-change-the-background-in-mac-os-x
# try:
# from appscript import app, mactypes
# app('Finder').desktop_picture.set(mactypes.File(file_loc))
# except ImportError:
# #import subprocess
# SCRIPT = """/usr/bin/osascript<<END
# tell application "Finder" to
# set desktop picture to POSIX file "%s"
# end tell
# END"""
# subprocess.Popen(SCRIPT%file_loc, shell=True)
else:
if first_run: #don't spam the user with the same message over and over again
sys.stderr.write("Warning: Failed to set wallpaper. Your desktop environment is not supported.")
sys.stderr.write("You can try manually to set Your wallpaper to %s" % file_loc)
return False
return True
except:
sys.stderr.write("ERROR: Failed to set wallpaper. There might be a bug.\n")
return False
def get_config_dir(self, app_name=APP_NAME):
if "XDG_CONFIG_HOME" in os.environ:
confighome = os.environ['XDG_CONFIG_HOME']
elif "APPDATA" in os.environ: # On Windows
confighome = os.environ['APPDATA']
else:
try:
from xdg import BaseDirectory
confighome = BaseDirectory.xdg_config_home
except ImportError: # Most likely a Linux/Unix system anyway
confighome = os.path.join(self.get_home_dir(),".config")
configdir = os.path.join(confighome,app_name)
return configdir
def get_home_dir(self):
if sys.platform == "cygwin":
home_dir = os.getenv('HOME')
else:
home_dir = os.getenv('USERPROFILE') or os.getenv('HOME')
if home_dir is not None:
return os.path.normpath(home_dir)
else:
raise KeyError("Neither USERPROFILE or HOME environment variables set.")
The get_desktop_environment method has been posted in another thread.

On a gnome desktop, you usually do this with gconf, either directly calling gconftool or using the gconf python module. The latter is in the link given by unutbu. The first method could be done like this.
import commands
command = "gconftool-2 --set /desktop/gnome/background/picture_filename --type string '/path/to/file.jpg'"
status, output = commands.getstatusoutput(command) # status=0 if success

In gnome, it is probably preferable to use the python binding of gconf directly:
import gconf
conf = gconf.client_get_default()
conf.set_string('/desktop/gnome/background/picture_filename','/path/to/filename.jpg')

On windows, you will need some trickery with pywin32, and the windows API, on 'linux' the answer will depend on which desktop is running - KDE, Gnome, or something more exotic. Under KDE (and maybe Gnome) you can probably send a message using D-Bus, which you could do without including any new libraries by using the command line tool dbus-send.
The other option would be to set the desktop wallpaper to a file which you then edit / replace from python - but this will probably only result in a change when the user logs in.

Firstly, import ctypes: it gives you access to windows components such as the screensaver, wallpapers, etc.
Then call
ctypes.windll.user32.SystemParametersInfoA(20, 0, the_complete_path_of_your_image, 0)
Make sure the path is the complete path of your image, not just the path from the active directory

There is a difference what SystemParametersInfo method to be called based on what if you are running on 64 bit or 32 bit OS. For 64 bit you have to use SystemParametersInfoW (Unicode) and for 32 bit SystemParametersInfoA (ANSI)
import struct
import ctypes
SPI_SETDESKWALLPAPER = 20
WALLPAPER_PATH = 'C:\\your_file_name.jpg'
def is_64_windows():
"""Find out how many bits is OS. """
return struct.calcsize('P') * 8 == 64
def get_sys_parameters_info():
"""Based on if this is 32bit or 64bit returns correct version of SystemParametersInfo function. """
return ctypes.windll.user32.SystemParametersInfoW if is_64_windows() \
else ctypes.windll.user32.SystemParametersInfoA
def change_wallpaper():
sys_parameters_info = get_sys_parameters_info()
r = sys_parameters_info(SPI_SETDESKWALLPAPER, 0, WALLPAPER_PATH, 3)
# When the SPI_SETDESKWALLPAPER flag is used,
# SystemParametersInfo returns TRUE
# unless there is an error (like when the specified file doesn't exist).
if not r:
print(ctypes.WinError())
change_wallpaper()

import ctypes,win32con
def getWallpaper():
ubuf = ctypes.create_unicode_buffer(512)
ctypes.windll.user32.SystemParametersInfoW(win32con.SPI_GETDESKWALLPAPER,len(ubuf),ubuf,0)
return ubuf.value
def setWallpaper(path):
changed = win32con.SPIF_UPDATEINIFILE | win32con.SPIF_SENDCHANGE
ctypes.windll.user32.SystemParametersInfoW(win32con.SPI_SETDESKWALLPAPER,0,path,changed)
Alternatively: (with SystemParametersInfoA)
def getWallpaper():
sbuf = ctypes.create_string_buffer(512) # ctypes.c_buffer(512)
ctypes.windll.user32.SystemParametersInfoA(win32con.SPI_GETDESKWALLPAPER,len(sbuf),sbuf,0)
return sbuf.value
def setWallpaper(path):
changed = win32con.SPIF_UPDATEINIFILE | win32con.SPIF_SENDCHANGE
ctypes.windll.user32.SystemParametersInfoA(win32con.SPI_SETDESKWALLPAPER,0,path.encode(),changed) # "".encode() = b""
Arguments are:
SystemParametersInfo(SetOrGet, GetBufferSize, SetBufferOrGetBuffer, SetChange)
The path has to be absolute, so if you're using something relative to your script, do:
path = os.path.abspath(path)
To see more stuff you can do with SystemParametersInfo, see the docs.
(near the bottom there's an example to change the mouse speed)
P.S. There are many answers already here, but they're leaving out the broadcasting you're supposed to do. Sure it works without it, but it's bad practice not to use it properly.
P.P.S And they only gave hard coded values, rather than the variables they come from.
Also note, i use 512 characters for the buffer size when getting the path, just to be more safe since paths might exceed 256. I doubt anyone will have paths as long as that though.
One more note. I've only tested the above examples in Python 3, but i don't think SystemParametersInfoA needs the .encode() in Python 2. (they updated strings in Python 3 to unicode i believe) The string in SystemParametersInfoW may need converting for Python 2.

I read all the answers and after searching for a while i found a easier solution.
Install the module named py-wallpaper.
pip install py-wallpaper
Import the module.
from wallpaper import set_wallpaper, get_wallpaper
set the wallpaper using set walpaper
set_wallpaper("location/to/image.jpg")
get the current wallpaper's path using get wallpaper
print(get_wallpaper())
thanks.

changing the background image of desktop
import ctypes
import os
SPI_SETDESKWALLPAPER = 20
ctypes.windll.user32.SystemParametersInfoA(SPI_SETDESKWALLPAPER, 0, 'your image path', 3)
#'C:\\Users\\Public\\Pictures\\abc.jpg'
it worked fine for me. windows10, python27

On Windows with python2.5 or higher, use ctypes to load user32.dll and call
import ctypes
ctypes.windll.user32.SystemParametersInfoW(20,0,"Path_wallpaper", 0)
speak("Background changed succesfully")

Just adding a small precision to ShivaGuntuku 's post :
In python 3 you should replace the 'A' by a 'W' in SytemParametersInfoA. Small exemple to change your desktop background in windows10 with python 3 :
import ctypes
import os
SPI_SETDESKWALLPAPER = 20
ctypes.windll.user32.SystemParametersInfoW(
SPI_SETDESKWALLPAPER, 0, 'C:\\Users\\godet\\OneDrive\\Images\\breaker_wall.jpg', 0)

this works for me
import ctypes
ctypes.windll.user32.SystemParametersInfoW(20,0,path:os.PathLike,3)

You can use this library PyWallpaper, worked for me on mac also.
To install type pip install PyWallpaper.
And then to change/set your wallpaper -
from PyWallpaper import change_wallpaper
change_wallpaper("/some_path/sample.jpg")