getdisplays.py

#!/usr/bin/python3

import dbus
bus = dbus.SessionBus()
request_iface = 'org.gnome.Mutter.DisplayConfig'

DisplayConfig = bus.get_object(request_iface,
                        '/org/gnome/Mutter/DisplayConfig')

data = DisplayConfig.GetCurrentState(dbus_interface=request_iface)

print("List of monitors:")
for d in data[1]:
    print ("Display: %s"%(d[2].get("display-name")))
    print ("  List of modes (* = current mode):")
    for mode in d[1]:
        print (" %dx%d %dHz  "%(mode[1], mode[2], mode[3]), end='')
        if mode[6].get("is-current"):
            print (" *")
        else:
            print ("")