dock.py

#!/usr/bin/python
from gi.repository import GLib, Gtk, Gdk
import Xlib.display

size = 167

def main():
    window = Gtk.Window() # Gtk.WINDOW_TOPLEVEL)
	
    window.set_default_size(size*0.68, Gdk.Screen.height())
    window.move(0, 0)
    window.set_type_hint(6) # Type DOCK
    window.show_all()

    xid = window.get_window().get_xid()

    display = Xlib.display.Display()

    window = display.create_resource_object("window", window.get_window().get_xid())
    window.change_property(
        display.intern_atom("_NET_WM_STRUT"),
        display.intern_atom("CARDINAL"),
        32, [size, 0, 0, 0])
    display.sync()

    Gtk.main()

main()