表达式 'abcab'.replace('a','yy') 的值为_________。 表达式 'abcab'.replace('a','yy',1) 的值为_________。

`'abcab'.replace('a','yy')` 的值为 `'yybcyyb'`，它将所有的 `'a'` 替换为 `'yy'`。

`'abcab'.replace('a','yy',1)` 的值为 `'yycab'`，它只将第一个 `'a'` 替换为 `'yy'`，因为第三个参数 `count` 指定了替换次数为 1。

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import re import subprocess import requests import json from pprint import pprint url = "https://www.bilibili.com/video/BV1fi4y1K7Na/?spm_id_from=333.1007.top_right_bar_window_default_collection.content.click&vd_source=4545a0e83c576b93b1abd0ca4e16ab4d" headers = { "referer": "https://www.bilibili.com/", "user-agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.51 Safari/537.36", "cookie":"i-wanna-go-back=-1; _uuid=C106610D104-6D27-6584-66E1-FCDE2859156A75277infoc; FEED_LIVE_VERSION=V8; home_feed_column=5; buvid3=D2AE610A6-6EE7-B48E-10C51-9E8269B10C88776898infoc; header_theme_version=CLOSE; DedeUserID=1852701166; DedeUserID__ckMd5=ac9474243bdd3627; nostalgia_conf=-1; CURRENT_PID=e16a0380-e1cd-11ed-a872-2f97008834b2; rpdid=|(k|k~u|)RY)0J'uY)kkl|m)m; b_ut=5; browser_resolution=1482-792; CURRENT_BLACKGAP=0; buvid_fp_plain=undefined; CURRENT_FNVAL=4048; b_nut=1683881044; hit-new-style-dyn=1; hit-dyn-v2=1; SESSDATA=3e3851ea%2C1704423625%2C1959b%2A72SteLEoaNhz8Q6ifKiYFGRpSBjpMp2TG-QWAao2iv2yR5ci81QOokmXevCx102rLpwUc9qgAAQgA; bili_jct=2ea1af9f8ae6f19867c8cd3dc1bfd047; fingerprint=dd5c1878758a4b317420b66dad49b677; b_lsid=97F1E5C5_1894440C9F1; buvid4=9D5A25A5-A648-0805-4C59-8178C4E4362B31067-023042319-0THAXXn9jKfRyf3rDh/fQA%3D%3D; buvid_fp=dd5c1878758a4b317420b66dad49b677; sid=7i4lnopc; bp_video_offset_1852701166=817021346575810700; PVID=1" } response = requests.get(url, headers=headers) name = re.findall('"title":"(.*?)"',response.text)[0].replace(' ','') html_data = re.findall('<script>window.__playinfo__=(.*?)</script>',response.text)[0] json_data = json.loads(html_data) #print(name) # print(html_data) # print(json_data) # pprint(json_data) audio_url = json_data['data']['dash']['audio'][0]['baseUrl'] video_url = json_data['data']['dash']['video'][0]['baseUrl'] # print(audio_url) # print(video_url) audio_content = requests.get(url=audio_url,headers=headers).content video_content = requests.get(url=video_url,headers=headers).content with open("D:\\study\\B站\\素材\\" + name + ".mp3", mode="wb") as audio: audio.write(audio_content) with open("D:\\study\\B站\\素材\\" + name + ".mp4", mode="wb") as video: video.write(video_content) cmd = f'ffmpeg -i D:\\study\\B站\\素材\\{name}.mp4 -i D:\\study\\B站\\素材\\{name}.mp3 -c:a aac -strict experimental D:\\study\\B站\\视频1080P\\{name}output.mp4' subprocess.run(cmd)

这段代码看起来是从Bilibili网站上下载视频和音频，并将它们合并为一个输出视频文件。代码中使用了requests库发送HTTP请求获取网页内容，使用re库进行正则表达式匹配提取视频标题和播放信息，使用json库解析JSON数据，然后使用subprocess库调用ffmpeg命令将音频和视频合并。

你有什么问题吗？