selection_sort.py

def selection_sort(lst):
    i = 0
    n = len(lst)
    while i < n:
        min_pos = i
        for j in range(i, n):
            if lst[j] < lst[min_pos]:
                min_pos = j

        target = lst[min_pos]

        j = min_pos
        while j > i:
            lst[j] = lst[j-1]
            j -= 1

        lst[i] = target
        i += 1

lst = [3,2,2,4,5,6,7,9,9,6,4,2,1]
selection_sort(lst)
print(lst)