@Override
  public String updateForBlueprintExport(String propertyName, String origValue, Map<String, Map<String, String>> properties, ClusterTopology topology) {
    return removeStackUnit(topology.getBlueprint().getStack(), serviceName, configType, propertyName, origValue);
  }
@return property value with removed unit
ambari-server/src/main/java/org/apache/ambari/server/controller/internal/UnitUpdater.java