(OS X) Universal script for setting the wallpaper. Works on 10.6-10.9

set-wallpaper-universal.py

#!/usr/bin/python
# Universal wallpaper script for 10.6 and up
from AppKit import NSWorkspace, NSScreen
from Foundation import NSURL
from platform import mac_ver
from subprocess import call
from os import system

# Set path here for 10.9
picture_path = "/Library/Desktop Pictures/Custom.jpg"

# http://stackoverflow.com/questions/1777344/how-to-detect-mac-os-version-using-python
v, _, _ = mac_ver()
v = float('.'.join(v.split('.')[:2]))
print v

if (v == 10.9):
    print str(v) + " detected..."
    file_url = NSURL.fileURLWithPath_(picture_path)
    options = {}
    ws = NSWorkspace.sharedWorkspace()
    for screen in NSScreen.screens():
    	(result, error) = ws.setDesktopImageURL_forScreen_options_error_(file_url, screen, options, None)
else:
    # Set path below for 10.6-10.8
    setSnowLeopardWallpaper="""wallpaper="/Library/Desktop Pictures/Custom.jpg"
    echo "Non-Mavericks OS detected..."
    for username in /Users/*
    do
        user=$(basename "${username}")
	    if [ ! "${user}" = "Shared" ];then 
            rm "$username"/Library/Preferences/com.apple.desktop.plist
            /usr/libexec/PlistBuddy -c "Add Background:ImageFilePath string $wallpaper" "$username"/Library/Preferences/com.apple.desktop.plist
            /usr/libexec/PlistBuddy -c "Add Background:default:ImageFilePath string $wallpaper" "$username"/Library/Preferences/com.apple.desktop.plist
	    else
		    :
	    fi
    done
    killall Dock"""
    system(setSnowLeopardWallpaper)