var BN=Import("zklBigNum");
fcn validateIBAN(iban){
iban=iban-" \t";
alphaNums.matches(iban) and (ibans.find(iban[0,2])==iban.len()) and
( BN((iban[4,*]+iban[0,4]).apply("toInt",36)) % 97 == 1 )
}