public static GeneralizedSemPm serializableInstance(){
  Dag dag=new Dag();
  GraphNode node1=new GraphNode("X");
  dag.addNode(node1);
  return new GeneralizedSemPm(Dag.serializableInstance());
}

public static GeneralizedSemPm serializableInstance ( ) { Dag dag = new Dag ( ) ; GraphNode node1 = new GraphNode ( "X" ) ; dag . addNode ( node1 ) ; return new GeneralizedSemPm ( Dag . serializableInstance ( ) ) ; }
generates a simple exemplar of this class to test serialization .
