code: def load(filename)
        begin
          new_config = YAML::load_file(filename)
          if new_config.kind_of?(Hash)
            @config = new_config
          else
            raise AdsCommon::Errors::Error,
                "Incorrect configuration file: '%s'" % filename
          end
        rescue TypeError => e
          raise AdsCommon::Errors::Error,
              "Error parsing configuration file: '%s' (%s)" % [filename, e]
        end
        return nil
      end
docs: Reads a configuration file into instance variable as a Ruby structure with
   the complete set of keys and values.
  
   Args:
   - filename: config file to be read (*String*)
  
   Raises:
   - <b>Errno::ENOENT</b> if the file does not exist.