curl --request GET \
  --url http://localhost/api/v3/countries

{
  "data": [
    {
      "id": 123,
      "name": "<string>",
      "iso_2": "<string>",
      "iso_3": "<string>",
      "iso_numeric": "<string>",
      "sort_order": 123,
      "states": [
        {
          "id": 123,
          "name": "<string>",
          "type": "<string>",
          "iso": "<string>",
          "iso_2_country": "<string>",
          "iso_2_country_state_code": "<string>",
          "sort_order": 123,
          "created_at": "<string>",
          "updated_at": "<string>"
        }
      ],
      "currency": "<string>",
      "created_at": "<string>",
      "updated_at": "<string>",
      "region": {
        "id": "<string>",
        "name": "<string>",
        "handle": "<string>",
        "is_default": "<string>"
      }
    }
  ]
}