public static void GraphHasCorrectNumberOfTreeEdges <K, T>(int expectedEdges, List <GraphVertex <K, T> > graph)
where K : IUnfoldableEdge
where T : IUnfoldablePlanarFace <K>
{
var alledges = GraphUtilities.GetAllTreeEdges(graph);
Assert.AreEqual(expectedEdges, alledges.Count);
Console.WriteLine("correct number of edges");
}