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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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])