#!/usr/bin/python

import subprocess

# close gnome-screensaver
subprocess.Popen(["gnome-screensaver-command", "--exit"])

# run application (put command which runs your application) 
player = subprocess.Popen("miro.run")

# wait till mplayer exits
player.wait()

# start gnome-screensaver again
subprocess.Popen("gnome-screensaver")