
# test = DoublyLinkedList()
# # remHead = DoublyLinkedList.remove_from_head(ListNode())


# test.add_to_head(1)
# test.add_to_head(2)
# test.add_to_head(3)
# test.add_to_head(4)
# print(len(test))
# test.remove_from_head()
# print(len(test))
