get datafeed

def read_stream(self, stream_id, since_epoch):
        ''' get datafeed '''
        response, status_code = self.__agent__.Messages.get_v4_stream_sid_message(
            sessionToken=self.__session__,
            keyManagerToken=self.__keymngr__,
            sid=stream_id,
            since=since_epoch
        ).result()
        self.logger.debug('%s: %s' % (status_code, response))
        return status_code, response