code: def unlock_sogou_callback_example(url, req, resp, img, identify_image_callback):
      
      # no use resp
      url_quote = url.split('weixin.sogou.com/')[-1]
      unlock_url = 'http://weixin.sogou.com/antispider/thank.php'
      data = {
          'c': identify_image_callback(img),
          'r': '%2F' + url_quote,
          'v': 5
      }
      headers = {
          'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8',
          'Referer': 'http://weixin.sogou.com/antispider/?from=%2f' + url_quote
      }
      r_unlock = req.post(unlock_url, data, headers=headers)
      r_unlock.encoding = 'utf-8'
      if not r_unlock.ok:
          raise WechatSogouVcodeOcrException(
              'unlock[{}] failed: {}'.format(unlock_url, r_unlock.text, r_unlock.status_code))
  
      return r_unlock.json()
docs: 手动打码解锁
  
      Parameters
      ----------
      url : str or unicode
          验证码页面 之前的 url
      req : requests.sessions.Session
          requests.Session() 供调用解锁
      resp : requests.models.Response
          requests 访问页面返回的，已经跳转了
      img : bytes
          验证码图片二进制数据
      identify_image_callback : callable
          处理验证码函数，输入验证码二进制数据，输出文字，参见 identify_image_callback_example
  
      Returns
      -------
      dict
          {
              'code': '',
              'msg': '',
          }