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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 int_to_string(number, alphabet, padding=None):
 """ Convert a number to a string, using the given alphabet. The output has the most significant digit first. """

    output = ""
    alpha_len = len(alphabet)
    while number:
        number, digit = divmod(number, alpha_len)
        output += alphabet[digit]
    if padding:
        remainder = max(padding - len(output), 0)
        output = output + alphabet[0] * remainder
    return output[::-1]