code: static Object logModule(boolean quiet, boolean verbose) {
      checkArgument(!(quiet && verbose), "quiet and verbose flags cannot be used at the same time!");
      Logger.Level logLevel;
      if (quiet) {
        return null;
      } else if (verbose) {
        logLevel = Logger.Level.FULL;
      } else {
        logLevel = Logger.Level.BASIC;
      }
      return new LogModule(logLevel);
    }
docs: Returns a log configuration module or null if none is needed.