This prototype should be used to create
    an iban object from iban correct string

    @param {String} iban

def baseN(num, b, numerals="0123456789abcdefghijklmnopqrstuvwxyz"):
    """
    This prototype should be used to create
    an iban object from iban correct string

    @param {String} iban
    """
    return ((num == 0) and numerals[0]) or \
        (baseN(num // b, b, numerals).lstrip(numerals[0]) + numerals[num % b])