code: private static Props loadConfigurationFromAzkabanHome() {
      final String azkabanHome = System.getenv("AZKABAN_HOME");
  
      if (azkabanHome == null) {
        logger.error("AZKABAN_HOME not set. Will try default.");
        return null;
      }
      if (!new File(azkabanHome).isDirectory() || !new File(azkabanHome).canRead()) {
        logger.error(azkabanHome + " is not a readable directory.");
        return null;
      }
  
      final File confPath = new File(azkabanHome, Constants.DEFAULT_CONF_PATH);
      if (!confPath.exists() || !confPath.isDirectory() || !confPath.canRead()) {
        logger.error(azkabanHome + " does not contain a readable conf directory.");
        return null;
      }
  
      return loadAzkabanConfigurationFromDirectory(confPath);
    }
docs: Loads the Azkaban property file from the AZKABAN_HOME conf directory
  
  @return Props instance