python for loop MIME sendmail发送相同的内容

import smtplib
from email.mime.text import MIMEText

def send_email(sender, receiver, subject, content):
    # 创建MIMEText对象
    message = MIMEText(content)

    # 设置发件人、收件人、主题
    message['From'] = sender
    message['To'] = receiver
    message['Subject'] = subject

    try:
        # 连接SMTP服务器
        smtp_obj = smtplib.SMTP('smtp.example.com', 25)
        # 登录SMTP服务器（如果需要的话）
        smtp_obj.login('username', 'password')
        # 发送邮件
        smtp_obj.sendmail(sender, receiver, message.as_string())
        print("邮件发送成功！")
    except smtplib.SMTPException as e:
        print("邮件发送失败：", e)

sender = 'sender@example.com'
receiver = 'receiver@example.com'
subject = 'Test Email'
content = 'This is a test email.'

send_email(sender, receiver, subject, content)