code: def set(self, section, val, data):
          
          val = val.lower()
          if section in self.__config:
              # logger.debug('set %s %s = %s', section, val, data)
              self.__config[section][val] = data
docs: Add a setting to the config
  
          `section` (mandatory) (string) the section name in the config E.g. `"agent"`
  
          `val` (mandatory) (string) the section name in the config E.g. `"host"`
  
          `data` (mandatory) (as appropriate) the new value for the `val`