'Mails out emails to the addresses listed in to_string.
to_string is split into a list which can be delimited by any of:
\';\', \',\', \':\' or any whitespace'

def send_email(self, to_string, subject, body):

    to_list = [x for x in re.split('\\s|,|;|:', to_string) if x]
    if (not to_list):
        return
    msg = ('From:    %s\nTo:    %s\nSubject:    %s\n\n%s' % (self._from_address, ',    '.join(to_list), subject, body))
    try:
        mailer = smtplib.SMTP(self._smtp_server, self._smtp_port)
        try:
            if self._smtp_user:
                mailer.login(self._smtp_user, self._smtp_password)
            mailer.sendmail(self._from_address, to_list, msg)
        finally:
            try:
                mailer.quit()
            except:
                logging.exception('mailer.quit()    failed:')
    except Exception:
        logging.exception('Sending    email    failed:')
