code: def send_email(sender, pw, to, subject, content, files=None, service='163'):
      
      se = EmailSender(from_=sender, pw=pw, service=service)
      se.send_email(to=to, subject=subject, content=content, files=files)
      se.quit()
docs: 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