如何在Python ftplib中查看FTP登录是否成功？

from ftplib import FTP

def ftp_login(host, username, password):
    try:
        # 创建FTP对象
        ftp = FTP(host)
        
        # 尝试登录
        ftp.login(username, password)
        
        # 如果登录成功，打印成功信息
        print("FTP登录成功")
        
        # 关闭连接
        ftp.quit()
        
        return True
    except Exception as e:
        # 如果登录失败，打印错误信息
        print(f"FTP登录失败: {e}")
        
        return False

# 示例调用
host = "ftp.example.com"
username = "your_username"
password = "your_password"

if ftp_login(host, username, password):
    print("登录成功")
else:
    print("登录失败")