pythonメールsendmail--smtplib【添付ファイル付き】

#!/usr/bin/env python
# -*- coding: UTF-8 -*-

from email.mime.multipart import MIMEMultipart
from email.mime.base import MIMEBase
from email.mime.text import MIMEText
 
from email.utils import COMMASPACE,formatdate
from email import encoders
 
import os
 
def send_mail(server, fro, to, subject, text, files=[]): 
    assert type(server) == dict 
    assert type(to) == list 
    assert type(files) == list 
 
    msg = MIMEMultipart() 
    msg['From'] = fro 
    msg['Subject'] = subject 
    msg['To'] = COMMASPACE.join(to) #COMMASPACE==', ' 
    msg['Date'] = formatdate(localtime=True) 
    msg.attach(MIMEText(text)) 
 
    for f in files: 
        part = MIMEBase('application', 'octet-stream') #'octet-stream': binary data 
        part.set_payload(open(f, 'rb').read()) 
        encoders.encode_base64(part) 
        part.add_header('Content-Disposition', 'attachment; filename="%s"' % os.path.basename(f)) 
        msg.attach(part) 
 
    import smtplib 
    smtp = smtplib.SMTP(server['name'], server['port']) 
    smtp.ehlo()
    smtp.starttls()
    smtp.ehlo()	
    smtp.login(server['user'], server['passwd']) 
    smtp.sendmail(fro, to, msg.as_string()) 
    smtp.close()
    
if __name__=='__main__':
    server = {'name':'mail.server.com', 'user':'chenxiaowu', 'passwd':'xxxx', 'port':25}
    fro = '[email protected]'
    to = ['[email protected]']
    subject = '      '
    text = 'mail content'
    files = ['top_category.txt']
    send_mail(server, fro, to, subject, text, files=files)

ネット上からいくつかの資料を探して、個別の誤りがあることはできなくて、上のコードはデバッグしてテストして合格しました