{ identifier: 'id',
  label: 'label',
  items: [
  
  //Folders
     { type:'folder', id:'f_1', label: 'Folder 1'},
     { type:'folder', id:'f_2', label: 'Folder 2'},
     { type:'folder', id:'f_3', label: 'Folder 3'},
     { type:'folder', id:'f_4', label: 'Folder 4'},
   //
     { type:'folder', id:'items', label: 'Primary',    
        children:[{_reference: 'item_1'},{_reference: 'item_2'},{_reference: 'item_3'}] },

  //Tenders
     {"type":"item","id":"item_1","label":"ITEM 1"},
{"type":"item","id":"item_2","label":"ITEM 2"},
{"type":"item","id":"item_3","label":"ITEM 3"}
]}