python下载油管视频

import time
from pytube import YouTube
import requests
# 需要自行创建三个文件夹 video audio cover

def getId(str):
    vid = str.split("=")[-1]
    print(vid)
    return vid


def down(vid):
    if not vid:
        print("地址有误，请重试")
        return
    start = time.time()
    yt = YouTube('https://youtu.be/%s' % vid)
    itags = [137, 399, 22]
    for i in itags:
        try:
            yt.streams.get_by_itag(i).download(output_path="./video", filename_prefix=vid + "_")
            if i != 22:
                yt.streams.get_by_itag(140).download(output_path="./audio", filename_prefix=vid + "_")
            break
        except:
            print("换清晰度..")
    end = time.time()
    downCover(vid)
    print("下载成功，用时%s秒" % (end - start))


def downCover(vid):
    try:
        # 1080p
        res = requests.get("https://img.youtube.com/vi/%s/maxresdefault.jpg" % vid)
        with open("./cover/%s.jpg" % vid, 'wb') as f:
            f.write(res.content)
    except:
        # 720p
        res = requests.get("https://img.youtube.com/vi/%s/hqdefault.jpg" % vid)
        with open("./cover/%s.jpg" % vid, 'wb') as f:
            f.write(res.content)


if __name__ == '__main__':
    URL = "https://www.youtube.com/watch?v=J4Ws9A-K14I"
    vid = getId(URL)
    down(vid)