code: public static LocalAlluxioMaster create(boolean includeSecondary) throws IOException {
      String workDirectory = uniquePath();
      FileUtils.deletePathRecursively(workDirectory);
      ServerConfiguration.set(PropertyKey.WORK_DIR, workDirectory);
      return create(workDirectory, includeSecondary);
    }
docs: Creates a new local Alluxio master with an isolated work directory and port.
  
  @param includeSecondary whether to start a secondary master alongside the regular master
  @return an instance of Alluxio master