nationalNO function
Implementation
String nationalNO(String bban, BbanStructure structure) {
final String value = [PartType.BANK_CODE, PartType.ACCOUNT_NUMBER]
.map((p) => structure.extractValueMust(bban, p))
.join("");
return (mod11(value, [5, 4, 3, 2, 7, 6, 5, 4, 3, 2]) % 10).toString();
}