实战代码 

import requests

if __name__ == '__main__':
    http_headers = {
                        'Accept': '*/*',
                        'Connection': 'keep-alive',
                        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36'
                    }

    try:
        resp = requests.get(url=item, headers=http_headers,timeout=10)
    except Exception as e:
        continue
    print("resp", resp.url)

以上代码未有重试机制，下面加上重试机制加以完善

def get_real_url(url,try_count = 1):
if try_count > 3:
    return url
try:
    rs = requests.get(url,headers=http_headers,timeout=10)
    if rs.status_code > 400:
        return get_real_url(url,try_count+1)
    return rs.url
except:
    return get_real_url(url, try_count + 1)