code: def request_log_level(self, req, msg):
          
          if msg.arguments:
              try:
                  self.log.set_log_level_by_name(msg.arguments[0])
              except ValueError, e:
                  raise FailReply(str(e))
          return req.make_reply("ok", self.log.level_name())
docs: Query or set the current logging level.
  
          Parameters
          ----------
          level : {'all', 'trace', 'debug', 'info', 'warn', 'error', 'fatal', \
                   'off'}, optional
              Name of the logging level to set the device server to (the default
              is to leave the log level unchanged).
  
          Returns
          -------
          success : {'ok', 'fail'}
              Whether the request succeeded.
          level : {'all', 'trace', 'debug', 'info', 'warn', 'error', 'fatal', \
                   'off'}
              The log level after processing the request.
  
          Examples
          --------
          ::
  
              ?log-level
              !log-level ok warn
  
              ?log-level info
              !log-level ok info