// 1) MenuDelegate.swift
  //Old
  func toCatalogPage(Catalog: Catalog)
  //New
  func toCatalogPage(ProductType: ProductType)
// 2) MenuViewController.swift
  //Old
  func toCatalogPage(Catalog: Catalog){
          CatalogMenuViewController?.parentCatalog = Catalog
          // ...
  }
  //New
  func toCatalogPage(ProductType: ProductType){
          CatalogMenuViewController?.parentProductType = ProductType
          // ...
  }
// 3) LeftMenuViewController.swift
  func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath){
    //...

    //Old
    MenuDelegate?.toCatalogPage(Catalog: catalogs[indexPath.row])
    //New
    MenuDelegate?.toCatalogPage(ProductType: ProductTypes[indexPath.row])

    //...
  }
// 4) CatalogMenuViewController.swift
    //Old
    var parentCatalog: Catalog = Catalog()
    //New
    var parentProductType: ProductType = ProductType()