python如何随机读取目录文件

import argparse
parser = argparse.ArgumentParser()
parser.add_argument('num',type=int,help="img numbers to random")
args = parser.parse_args()
import random
import os
path="/home/train/disk/data/yulan_park_expand"
imgs = []
for x in os.listdir(path):
    if x.endswith('jpg'):
imgs.append(x)
selected_imgs=random.sample(imgs,k=args.num)
print(selected_imgs)
from shutil import copyfile
for img in selected_imgs:
    src=os.path.join(path,img)
    dst=os.path.join(path,"../for_bitmain/"+img)    
    copyfile(src,dst)
print("copy done")