怎么使用python检测代理IP是否有效

####
import requests
url = "http://httpbin.org/ip"
proxies = {
      'http':'http://168.168.168.168:88888',
       'https':'http://168.168.168.168:88888'
}
headers = {
       'User-Agent':'Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_8; en-us) AppleWebKit/534.50 (KHTML, like Gecko)
        Version/5.1 Safari/534.50'
}
try:
    resp = requests.get(url,headers=headers,proxies=proxies,timeout=10)
    print(resp.text)
except Exception as e:
    print(f"请求失败，代理IP无效！{e}")

######
api_url = "***************" 
proxy_text = requests.get(api_url).text
proxy_list = proxy_ip.split('\r\n') 
for proxy  in proxy_list:
      proxies = {
               'http': 'http://'+proxy,
               'https': 'http://' + proxy
    }