wagons = [0, 1, 2, 3, 4] wagons[0] # 0 (single item) wagons[:1] # [0] (list with item 0)
wagons = [0, 1, 2, 3, 4] wagons[1:] # [1, 2, 3, 4] (list)
wagons = [0, 1, 2, 3, 4] wagons[:-1] # [0, 1, 2, 3] (list)
wagons = [0, 1, 2, 3, 4] wagons[-1] # 4 (single item) wagons[-1:] # [4] (list with item 4)