input: 
  from typing import List
  
  def sum_list(input_list: List[int]) -> int:
      """
      Calculate the sum of all items in the list.
      >>> sum_list([1, 2, 3, 4, 5])
      15
      >>> sum_list([])
      0
      >>> sum_list([-1, 0, 1])
      0
      """
      sum_result = 0
      for item in input_list:
          sum_result += item
      return sum_result
  
output:     sum_result = 0
      for item in input_list:
          sum_result += item
      return sum_result