Send mail with attachment in python

sendmail.py

import smtplib
from email.MIMEMultipart import MIMEMultipart
from email.MIMEBase import MIMEBase
from email.MIMEText import MIMEText
from email.Utils import COMMASPACE, formatdate
from email import Encoders
import os
import time
import random

def generate_message_id(msg_from):
    domain = msg_from.split("@")[1]
    r = "%s.%s" % (time.time(), random.randint(0, 100))
    mid = "<%s@%s>" % (r, domain)
    return mid

def send_mail(msg_from, to, subject, text,
    files=[],server="localhost", debug=False):
    assert type(to)==list
    assert type(files)==list

    msg = MIMEMultipart()
    msg['From'] = msg_from
    msg['To'] = COMMASPACE.join(to)
    msg['Date'] = formatdate(localtime=True)
    msg['Subject'] = subject

    text = text.encode("utf-8")
    text = MIMEText(text, 'plain', "utf-8")
    msg.attach(text)

    msg.add_header('Message-ID', generate_message_id(msg_from))

    for file in files:
        part = MIMEBase('application', "octet-stream")
        part.set_payload( open(file,"rb").read() )
        Encoders.encode_base64(part)
        part.add_header('Content-Disposition', 'attachment; filename="%s"'
                       % os.path.basename(file))
        msg.attach(part)

    if not debug:
        smtp = smtplib.SMTP(server)
        smtp.sendmail(msg_from, to, msg.as_string())
        smtp.close()

    return msg

#sendMail(["destination@dest.kio"], "hello","cheers", ["photo.jpg","memo.sxw"])