flutter GoogleMap() combine markers code example

Example: set markers in google_map_flutter

List<Marker> _markers = []
    
    _markers.add(
      Marker(
      markerId: MarkerId('SomeId'),
      position: LatLng(38.123,35.123),
      infoWindow: InfoWindow(
      title: 'The title of the marker'
      )
     )
   );
   
   GoogleMap(
      initialCameraPosition: CameraPosition(
        target: LatLng(38.9647,35.2233),
        zoom: 9.0,
      ),
      mapType: MapType.normal,
      markers: Set<Marker>.of(_markers),
      onMapCreated: (GoogleMapController controller) {
        _controller.complete(controller);
      },
    )