input: def calculate_average(nums: List[int]) -> float:
      """ Calculate the average of a list of five numbers provided by the user.
      >>> calculate_average([10, 20, 30, 40, 50])
      30.0
      >>> calculate_average([5, 15, 25, 35, 45])
      25.0
      """
output:     return sum(nums) / len(nums)