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Question

我使用Gmail SMTP以Python发送电子邮件，但有时应用程序可能会长时间闲置。

如何确保会话未过期？这是我的代码：

def send_email(user, pwd, recipient, subject, body):
    import smtplib

    gmail_user = user
    gmail_pwd = pwd
    FROM = user
    TO = recipient if type(recipient) is list else [recipient]
    SUBJECT = subject
    TEXT = body

    # Prepare actual message
    message = """\From: %s\nTo: %s\nSubject: %s\n\n%s
    """ % (FROM, ", ".join(TO), SUBJECT, TEXT)
    try:
            server = smtplib.SMTP("smtp.gmail.com", 587)
            server.ehlo()
            server.starttls()
            server.login(gmail_user, gmail_pwd)
            server.sendmail(FROM, TO, message)
            server.close()
            print 'successfully sent the mail'
    except:
            print "failed to send mail"

我可以随时重复使用服务器会话，还是可以在5小时后过期？