{
  "columns": [
    {
      "label": "Test Column 1",
      "fromKey": "data",
      "sortable": true,
      "custom": "cellWithIndex",
      "type": "CUSTOM"
    }
  ],

  "rows": [
    { "data": "dog" },
    { "data": "cat" },
    { "data": "mouse" }
  ]
}