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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):
 """ Calculate and return control digit for given list of digits based on ISO7064, MOD 11,10 standard. """

    remainder = 10
    for digit in digits:
        remainder = (remainder + digit) % 10
        if remainder == 0:
            remainder = 10
        remainder = (remainder * 2) % 11

    control_digit = 11 - remainder
    if control_digit == 10:
        control_digit = 0
    return control_digit