SMTP未与python ftplib连接

import smtplib
from email.mime.text import MIMEText

# 邮件内容
msg = MIMEText('这是一封测试邮件', 'plain', 'utf-8')
msg['Subject'] = '测试邮件'
msg['From'] = 'sender@example.com'
msg['To'] = 'recipient@example.com'

# 发送邮件
smtp_server = 'smtp.example.com'
smtp_port = 25
smtp_username = 'your_username'
smtp_password = 'your_password'

try:
    with smtplib.SMTP(smtp_server, smtp_port) as smtp:
        smtp.login(smtp_username, smtp_password)
        smtp.sendmail(msg['From'], msg['To'], msg.as_string())
    print('邮件发送成功')
except Exception as e:
    print('邮件发送失败:', str(e))

from ftplib import FTP

# 连接FTP服务器
ftp_server = 'ftp.example.com'
ftp_port = 21
ftp_username = 'your_username'
ftp_password = 'your_password'

try:
    with FTP() as ftp:
        ftp.connect(ftp_server, ftp_port)
        ftp.login(ftp_username, ftp_password)

        # 上传文件
        local_file = 'local_file.txt'
        remote_file = 'remote_file.txt'
        with open(local_file, 'rb') as file:
            ftp.storbinary(f'STOR {remote_file}', file)
        print('文件上传成功')
except Exception as e:
    print('文件上传失败:', str(e))