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
}