def test_remove_items():
repo = Repository()
repo.add_item(0)
repo.add_item(1)
repo.add_item(1)
repo.add_item(1)
repo.remove_item(lambda item: item == 1)
assert repo.get_items() == [0, 1, 1]
repo.undo()
assert repo.get_items() == [0, 1, 1, 1]
repo.remove_items(lambda item: item == 1)
assert repo.get_items() == [0]
repo.undo()
assert repo.get_items() == [0, 1, 1, 1]
