ion('add employee');
            }
          }
        })
          .add(new go.TextBlock('Add Employee')),
        go.GraphObject.build('ContextMenuButton', {
          click: (e, button) => {
            // remove the whole subtree, including the node itself
            const node = button.part.adornedPart;
            if (node !== null) {
              myDiagram.startTransaction('toggle assistant');
              myDiagram.model.setDataProperty(node.data, 'isAssistant', !node.data.isAssistant);
         