def response(self, response):
if self.out_properties:<EOL><INDENT>return Success(self.out_properties)<EOL><DEDENT>if not response:<EOL><INDENT>return Failure("<STR_LIT>")<EOL><DEDENT>return self._parse_response(response)<EOL>
Process a client reponse.

        :Parameters:
            - `response`: the response from the client.
        :Types:
            - `response`: `bytes`

        :return: a challenge, a success indicator or a failure indicator.
        :returntype: `sasl.Challenge`, `sasl.Success` or `sasl.Failure`