def test_add_neighbor(self):
print('Test: test_add_neighbor')
n, n1 = Node(0), Node(1)
print('Test: Invalid input')
self.assertRaises(ValueError, n.add_neighbor, None)
self.assertRaises(ValueError, n.add_neighbor, n)
print('Test: general case')
n.add_neighbor(n1)
self.assertEqual(n.neighbors[0][0].key, n1.key)
print('Success: test_add_neighbor')
def test_remove_neighbor(self):
print('Test: test_remove_neighbor')
n, n1 = Node(0), Node(1)
print('Test: remove a non-existent node')
self.assertRaises(ValueError, n.remove_neighbor, 1)
print('Test: general case')
n.add_neighbor(n1)
self.assertEqual(n.neighbors[0][0].key, n1.key)
n.remove_neighbor(1)
self.assertEqual(len(n.neighbors), 0)
print('Success: test_remove_neighbor')