List extra items groups

{
  "data": [
    {
      "id": 0,
      "order": 10000,
      "name": "string",
      "disabled": false,
      "input_hint": "",
      "input_template": "",
      "created_at": "2019-08-24T14:15:22Z",
      "updated_at": "2019-08-24T14:15:22Z",
      "table_type": "Customer",
      "created_by_id": 0,
      "updated_by_id": 0,
      "extra_items": [
        {
          "id": 0,
          "name": "string",
          "internal_key": "string",
          "required": false,
          "created_at": "2019-08-24T14:15:22Z",
          "updated_at": "2019-08-24T14:15:22Z",
          "order": 10000,
          "input_hint": "",
          "data_type": "Integer",
          "unit": "Age",
          "created_by_id": 0,
          "updated_by_id": 0,
          "extra_item_group_id": 0,
          "extra_item_options": [
            {
              "internal_key": "string",
              "value": 0,
              "extra_item": {
                "id": 0,
                "name": "string",
                "internal_key": "string",
                "group_id": 0,
                "data_type": "Integer",
                "unit": "Age"
              }
            }
          ]
        }
      ]
    }
  ],
  "total": 0
}