async def _event_listener(self):
        """Listens for sink and server events from the server."""
        async for event in self.pulse.subscribe_events("sink", "server"):
            # Sink events will signify volume changes
            if event.facility == "sink":
                # There's been a change to available sinks
                # Update default sink details before querying the sink
                if event.t in ("new", "remove"):
                    await self.get_server_info()
                await self.get_sink_info()
            # Server events include when the default sink changes
            elif event.facility == "server":
                await self.get_server_info()
Listens for sink and server events from the server.
libqtile/widget/pulse_volume.py