def test_clean_void(self):
s_list = LinkedList()
s_list.clean()
ht = s_list.get_head_tail()
data = ht + s_list.list_all_nodes()
res = [None, None]
self.assertEqual(data, res)
def test_clean_one(self):
n1 = Node(1)
s_list = LinkedList()
s_list.add_in_tail(n1)
s_list.clean()
ht = s_list.get_head_tail()
data = ht + s_list.list_all_nodes()
res = [None, None]
self.assertEqual(data, res)