code: def notify(self, new_issues, existing_issues, fixed_issues):
          
          if len(new_issues + existing_issues + fixed_issues) > 0:
              maxlen = max(len(x['properties']['source']) for x in (new_issues + existing_issues + fixed_issues)) + 2
              text_tmpl = get_template('domain_hijacking.txt')
              html_tmpl = get_template('domain_hijacking.html')
              issues_text = text_tmpl.render(
                  new_issues=new_issues,
                  existing_issues=existing_issues,
                  fixed_issues=fixed_issues,
                  maxlen=maxlen
              )
              issues_html = html_tmpl.render(
                  new_issues=new_issues,
                  existing_issues=existing_issues,
                  fixed_issues=fixed_issues,
                  maxlen=maxlen
              )
  
              try:
                  send_notification(
                      subsystem=self.name,
                      recipients=[NotificationContact('email', addr) for addr in self.recipients],
                      subject=self.subject,
                      body_html=issues_html,
                      body_text=issues_text
                  )
              except Exception as ex:
                  self.log.exception('Failed sending notification email: {}'.format(ex))
docs: Send notifications (email, slack, etc.) for any issues that are currently open or has just been closed
  
          Args:
              new_issues (`list` of :obj:`DomainHijackIssue`): List of newly discovered issues
              existing_issues (`list` of :obj:`DomainHijackIssue`): List of existing open issues
              fixed_issues (`list` of `dict`): List of fixed issues
  
          Returns:
              None