快速排序 python版

def qsort(data, l, r):    if l < r:        # 取左边的数作为分界点        tmp = data[l]        lt = l        rt = r        while lt < rt:            # 找右边比tmp小的数            while data[rt] >= tmp and rt > lt:                rt -= 1            data[lt] = data[rt]            # 找左边比tmp大的数            while data[lt] <= tmp and lt < rt:                lt += 1            data[rt] = data[lt]        data[lt] = tmp        qsort(data, l, lt-1)        qsort(data, lt+1, r)    else:        return