input: Write a function to unpack a list of three elements and print each element.
  assert unpack_and_print([1, 2, 3]) == (1, 2, 3)
  assert unpack_and_print(['a', 'b', 'c']) == ('a', 'b', 'c')
  assert unpack_and_print([True, False, None]) == (True, False, None)
output: def unpack_and_print(lst):
      a, b, c = lst
      print(a)
      print(b)
      print(c)
      return a, b, c