怎么检测域名是不是有问题

import socket
import ssl
import datetime

def check_domain(domain):
    # DNS解析检测
    try:
        ip = socket.gethostbyname(domain)
        print(f"DNS解析成功: {domain} -> {ip}")
    except socket.gaierror:
        print(f"DNS解析失败: {domain}")

    # SSL证书检测
    context = ssl.create_default_context()
    with socket.create_connection((domain, 443)) as sock:
        with context.wrap_socket(sock, server_hostname=domain) as ssock:
            cert = ssock.getpeercert()
            not_after = datetime.datetime.strptime(cert['notAfter'], '%b %d %H:%M:%S %Y %Z')
            not_before = datetime.datetime.strptime(cert['notBefore'], '%b %d %H:%M:%S %Y %Z')
            print(f"SSL证书有效期: {not_before} - {not_after}")
            if not_after < datetime.datetime.now():
                print("SSL证书已过期")
            else:
                print("SSL证书有效")

# 示例调用
check_domain("example.com")