def test_add_edge(self):
graph = Graph("my graph")
graph.add_vertex("A")
graph.add_vertex("B")
graph.add_edge("A", "B")
self.assertEqual(1, len(graph.edges()))
graph.add_edge("X", "Y")
self.assertEqual(2, len(graph.edges()))
self.assertEqual(4, len(graph.vertices()))
def test_add_vertex(self):
graph = Graph("my graph")
graph.add_vertex("A")
self.assertEqual(['A'], graph.vertices())
