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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_log_level(self, log_level=None):
 """Set the current log level for the daemon The `log_level` parameter must be in [DEBUG, INFO, WARNING, ERROR, CRITICAL] In case of any error, this function returns an object containing some properties: '_status': 'ERR' because of the error `_message`: some more explanations about the error Else, this function returns True :param log_level: a value in one of the above :type log_level: str :return: see above :rtype: dict """

        if log_level is None:
            log_level = cherrypy.request.json['log_level']

        if log_level not in ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL']:
            return {'_status': u'ERR',
                    '_message': u"Required log level is not allowed: %s" % log_level}

        alignak_logger = logging.getLogger(ALIGNAK_LOGGER_NAME)
        alignak_logger.setLevel(log_level)
        return self.get_log_level()