アルゴリズムクイックリファレンス：クイックソート

quick_sort.py

def quick_sort(target):
    if len(target) <= 1:
        return target

    pivot = target[0]
    left = []
    right = []
    for x in xrange(1, len(target)):
        if target[x] <= pivot:
            left.append(target[x])
        else:
            right.append(target[x])

    left = quick_sort(left)
    right = quick_sort(right)
    mid = [pivot]
    return left + mid + right