input: def increment_elements(lst: list):
      """Return a list where each item is increased by 1.
      >>> increment_elements([1, 2, 3])
      [2, 3, 4]
      >>> increment_elements([5, 3, 5, 2, 3, 3, 9, 0, 123])
      [6, 4, 6, 3, 4, 4, 10, 1, 124]
      """
output:     return [x + 1 for x in lst]