input: py
  def sum_list(lst: list) -> int:
      """Calculate the sum of elements in a list.
      >>> sum_list([1, 2, 3, 4, 5])
      15
      """
      total = 0
      for num in lst:
          total += num
      return total
  
output:     total = 0
      for num in lst:
          total += num
      return total