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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def send_email(sender, pw, to, subject, content, files=None, service='163'):
 """send email, recommended use 163 mailbox service, as it is tested. :param sender: str email address of sender :param pw: str password for sender :param to: str email addressee :param subject: str subject of email :param content: str content of email :param files: list path list of attachments :param service: str smtp server address, optional is ['163', 'qq'] :return: None """

    se = EmailSender(from_=sender, pw=pw, service=service)
    se.send_email(to=to, subject=subject, content=content, files=files)
    se.quit()