def test_heap_iteration(self):
     heap = Heap(max_heap())
     self.assertEqual([int(str(n)) for n in heap.breadth()], [17, 15, 10, 6, 10, 7])
     self.assertEqual([int(str(n)) for n in heap], [17, 15, 10, 6, 10, 7])
     self.assertEqual(heap.flatten(), [17, 15, 10, 6, 10, 7])