def test_al(): exercise_graph(ods.AdjacencyLists)
def test_am(): exercise_graph(ods.AdjacencyMatrix)
def test_al(): exercise_graph(ods.AdjacencyLists)
def test_al(): exercise_graph(ods.AdjacencyLists)
def test_am(): exercise_graph(ods.AdjacencyMatrix)
def test_al(): exercise_graph(ods.AdjacencyLists)