code: def get_items(self):
          
          itemlist = []
          def add_to_itemlist(item):
              for index in range(item.childCount()):
                  citem = item.child(index)
                  itemlist.append(citem)
                  add_to_itemlist(citem)
          for tlitem in self.get_top_level_items():
              add_to_itemlist(tlitem)
          return itemlist
docs: Return items (excluding top level items)