cellsrenderer: function(){ return 'Menu' },
          buttonclick: menu_renderer }
      ];
      var custom_grid_options = {
        columngroups: [
          { text: 'Document', name: 'Document', align: 'center' },
          { text: 'Entity', name: 'Entity', align: 'center' }
        ]
      };
      draw_grid(".jqxgrid", datafields, columns, true, null, custom_grid_options);

    });
  </script>
{% endblock %}
