如何使用Python判断给定的域名是使用HTTP还是HTTPS协议？

import socket

def get_protocol(domain):
    """
    判断域名使用的协议（http或https）

    args:
        domain (str): 需要判定的域名

    returns:
        str: 识别出的协议（"http"或"https"）
    """

    try:
        # 尝试连接到http端口
        sock = socket.socket(socket.af_inet, socket.sock_stream)
        sock.settimeout(1)
        sock.connect((domain, 80))
        sock.close()
        return "http"
    except socket.error:
        pass

    try:
        # 尝试连接到https端口
        sock = socket.socket(socket.af_inet, socket.sock_stream)
        sock.settimeout(1)
        sock.connect((domain, 443))
        sock.close()
        return "https"
    except socket.error:
        pass

    # 均未连接成功，则无法识别协议
    return none

domain = "www.baidu.com"
protocol = get_protocol(domain)

if protocol == "http":
    url = "http://" + domain
elif protocol == "https":
    url = "https://" + domain
else:
    # 无法识别协议，需要人工判断
    print("无法识别协议，请手动指定：")
    url = input()