Value MUST be part of code list 'ISO 3166-1:Alpha2 Country codes'.
/ubl:CatalogueRequest/cac:CatalogueRequestLine/cac:RequiredItemLocationQuantity/cac:ApplicableTerritoryAddress/cac:Country/cbc:IdentificationCode(some $code in $clISO3166 satisfies $code = normalize-space(text()))