def test_linked_list_insert_after_end():
ll = LinkedList()
ll.append('a')
ll.append('b')
ll.insertAfter('b', 'c')
actual = str(ll)
expected = "{ a } -> { b } -> { c } -> NULL"
assert actual == expected
def test_insertAfter():
node = Node(6)
linked2 = LinkedList(node)
linked2.insert(5)
linked2.insert(4)
linked2.insertAfter(5,9)
actual = str(linked2)
expected = '{4} -> {5} -> {9} -> {6} -> Null'
assert actual == expected
