def insertion_sort(items):
    """
    Sort items with an insertion sort.
    """
    last = 0
    for index in range(1, len(items)):
        if items[index] < items[last]:
            temp = items[index]
            for sorted_index in reversed(range(0, last + 1)):
                if temp < items[sorted_index]:
                    items[sorted_index + 1] = items[sorted_index]
                    items[sorted_index] = temp
        last += 1
    return items