QTdragon HD with MDI issue

    def SHUT_SYSTEM_DOWN_PROMPT(self):         import subprocess         try:             try:                 subprocess.call('gnome-session-quit --power-off', shell=True)             except:                 try:                     subprocess.call('xfce4-session-logout', shell=True)                 except:                     try:                         subprocess.call('systemctl poweroff', shell=True)                     except:                         raise         except Exception as e:             LOG.warning("Couldn't shut system down: {}".format(e))