AttributeError: module 'smtplib' has no attribute 'SMTP_SSL'

这个错误通常是由于导入的smtplib模块中没有SMTP_SSL属性引起的。这可能是因为您的Python版本太旧，不支持SMTP_SSL。您可以尝试使用SMTP类而不是SMTP_SSL类来发送电子邮件。以下是一个示例代码片段，演示如何使用SMTP类发送电子邮件：

import smtplib
from email.mime.text import MIMEText

mail_host = "smtp.qq.com"
mail_user = "your_email_address"
mail_pass = "your_email_password"
sender = 'your_email_address'
receivers = ['receiver_email_address']

message = MIMEText('This is a test email.')
message['From'] = sender
message['To'] = receivers[0]
message['Subject'] = 'Test Email'

try:
    smtpObj = smtplib.SMTP(mail_host, 25)
    smtpObj.login(mail_user, mail_pass)
    smtpObj.sendmail(sender, receivers, message.as_string())
    print("Email sent successfully")
except smtplib.SMTPException as e:
    print("Error: unable to send email", e)