如何在Python中保存电子邮件附件或告诉我没有附件？

import email
import imaplib

# 连接到邮件服务器
mail = imaplib.IMAP4_SSL('imap.example.com')
mail.login('your_email@example.com', 'your_password')
mail.select('inbox')

# 搜索邮件
result, data = mail.search(None, 'ALL')
email_ids = data[0].split()

# 遍历邮件
for email_id in email_ids:
    result, data = mail.fetch(email_id, '(RFC822)')
    raw_email = data[0][1]
    email_message = email.message_from_bytes(raw_email)

    # 检查是否有附件
    if email_message.get_content_maintype() == 'multipart':
        for part in email_message.walk():
            if part.get_content_maintype() == 'multipart' or part.get('Content-Disposition') is None:
                continue
            filename = part.get_filename()
            if filename:
                # 保存附件
                with open(filename, 'wb') as f:
                    f.write(part.get_payload(decode=True))
                print(f'Saved attachment: {filename}')
    else:
        print('No attachment')

# 关闭连接
mail.logout()