用python从微信视频号下载视频

微信视频号下载需要模拟用户登录并获取视频的链接，然后通过 HTTP 请求下载视频。以下是一个简单的 Python 实现：

import requests
import json
import re

# 模拟登录，获取 cookie
def login(username, password):
    url = 'https://mp.weixin.qq.com/cgi-bin/login?lang=zh_CN'
    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3',
        'Referer': 'https://mp.weixin.qq.com/'
    }
    data = {
        'username': username,
        'pwd': password,
        'imgcode': '',
        'f': 'json'
    }
    session = requests.Session()
    r = session.post(url, headers=headers, data=data)
    if r.status_code == 200:
        res = json.loads(r.text)
        if res['base_resp']['err_msg'] == 'ok':
            return session.cookies.get_dict()

# 获取视频链接
def get_video_link(url, cookie):
    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3',
        'Referer': url,
        'Cookie': '; '.join([f'{k}={v}' for k, v in cookie.items()])
    }
    r = requests.get(url, headers=headers)
    if r.status_code == 200:
        m = re.search(r'vid:\s*\'(.+?)\'', r.text)
        if m:
            vid = m.group(1)
            api_url = f'https://mp.weixin.qq.com/mp/videoplayer?action=get_mp_video_play_url&preview=0&__biz=MzAxNTI4MTM3Mw==&mid=2650820022&idx=1&vid={vid}&uin=&key=&pass_ticket=&wxtoken=&appmsg_token=&x5=0&f=json'
            r = requests.get(api_url, headers=headers)
            if r.status_code == 200:
                res = json.loads(r.text)
                if res['base_resp']['err_msg'] == 'ok':
                    return res['url_info'][0]['url']

# 下载视频
def download_video(url, cookie, filename):
    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3',
        'Referer': url,
        'Cookie': '; '.join([f'{k}={v}' for k, v in cookie.items()])
    }
    r = requests.get(url, headers=headers, stream=True)
    if r.status_code == 200:
        with open(filename, 'wb') as f:
            for chunk in r.iter_content(1024):
                f.write(chunk)

# 使用示例
cookie = login('your_username', 'your_password')
url = 'https://mp.weixin.qq.com/s/1QZjVp6YwYVlKQs1jzVX1g'
video_link = get_video_link(url, cookie)
download_video(video_link, cookie, 'video.mp4')

请注意，上述代码仅供参考，具体实现可能需要根据实际情况进行修改。同时，下载他人视频涉及到版权问题，请谨慎使用。