code: def last_ehlo_response(self, response: SMTPResponse) -> None:
          
          extensions, auth_methods = parse_esmtp_extensions(response.message)
          self._last_ehlo_response = response
          self.esmtp_extensions = extensions
          self.server_auth_methods = auth_methods
          self.supports_esmtp = True
docs: When setting the last EHLO response, parse the message for supported
          extensions and auth methods.