How to add text to a graph after drawing using JSL?

[#1]

Add the text "txt1" at the top left of the image coordinates (100,100)

Thanks!

dt = Current Data Table();
P1 = dt << Graph Builder(
	Show Control Panel( 0 ),
	Variables( X( :age ), Y( :sex ) ),
	Elements( Heatmap( X, Y, Legend( 2 ) ) )
	//, Text( Center Justified, {100, 100  }, "txt1"); ??
);

[#2]

nw = Report( gb )[Graph Builder Box( 1 )];


dy = New Table( "K", Add Rows( 2 ), New Column( "A", Expression ), New Column( "B", Expression ) );
dy[1, 1] = nw;

[#3]

how can use the jsl

Thank Jim!

,SendToReport(
	Dispatch(
		{},
		"Graph Builder",
		FrameBox,
		{Add Graphics Script( 2, Description：( "" ), Text( Center Justified, {50, 50}, "Big Class" ) )}
	)
);