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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 checksum(digits, scale):
 """ Calculate checksum of Norwegian personal identity code. Checksum is calculated with "Module 11" method using a scale. The digits of the personal code are multiplied by the corresponding number in the scale and summed; if remainder of module 11 of the sum is less than 10, checksum is the remainder. If remainder is 0, the checksum is 0. https://no.wikipedia.org/wiki/F%C3%B8dselsnummer """

    chk_nbr = 11 - (sum(map(operator.mul, digits, scale)) % 11)
    if chk_nbr == 11:
        return 0
    return chk_nbr