Stable quicksort

def quicksort(list, left, right):
    if left == right - 1:
        return
    pivot = list[randint(left, right)]

    lesser = []
    greater = []
    for i in range(left, right):
        if list[i] < pivot:
            lesser.append(list[i])
        else:
            greater.append(list[i])

    for i in range(len(lesser)):
        list[left + i] = lesser[i]
    for i in range(len(greator)):
        list[left + len(lesser) + i] = greater[i]
    # тут освобождаем память, занятую lesser и greater.
    quicksort(list, left, left + len(lesser))
    quicksort(list, left + len(lesser), right)