test-mpris.py

import pydbus
from gi.repository import GLib

def list_player_names():
    bus = pydbus.SessionBus()
    for n in bus.dbus.ListNames():
        if n.startswith("org.mpris.MediaPlayer2"):
            yield bus.get(n, "/org/mpris/MediaPlayer2")

def callback(self, metadata):
    print(metadata['xesam:album'])
    print(metadata['xesam:title'])

if __name__ == "__main__":
    pithos = next(list_player_names())
    pithos.TrackMetadataChanged.connect(callback)
    GLib.MainLoop().run()