input: 
  from typing import List
  
  def insertion_sort(list: List[int]) -> List[int]:
      """ Implement the insertion sort algorithm.
      >>> insertion_sort([4, 2, 7, 1, 3])
      [1, 2, 3, 4, 7]
      >>> insertion_sort([9, 5, 8, 3, 1])
      [1, 3, 5, 8, 9]
      """
  
output:     for i in range(1, len(list)):
          key = list[i]
          j = i - 1
          while j >= 0 and key < list[j]:
              list[j + 1] = list[j]
              j -= 1
          list[j + 1] = key
      return list