def test_append():
doubly_linked_list = DoublyLinkedList()
doubly_linked_list.append(3)
doubly_linked_list.append(4)
assert doubly_linked_list.size() == 2
assert doubly_linked_list.get(0) == 3
assert doubly_linked_list.get(1) == 4
def test_insert_empty():
doubly_linked_list = DoublyLinkedList()
doubly_linked_list.insert(3, 0)
assert doubly_linked_list.size() == 1
assert doubly_linked_list.get(0) == 3
def test_init():
linked_list = DoublyLinkedList()
linked_list.append(3)
assert linked_list.size() == 1
assert linked_list.get(0) == 3
def test_append_empty():
doubly_linked_list = DoublyLinkedList()
doubly_linked_list.append(1)
assert doubly_linked_list.size() == 1
assert doubly_linked_list.get(0) == 1