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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_identity_card_number(characters):
 """ Calculates and returns a control digit for given list of characters basing on Identity Card Number standards. """

    weights_for_check_digit = [7, 3, 1, 0, 7, 3, 1, 7, 3]
    check_digit = 0

    for i in range(3):
        check_digit += weights_for_check_digit[i] * (ord(characters[i]) - 55)

    for i in range(4, 9):
        check_digit += weights_for_check_digit[i] * characters[i]

    check_digit %= 10

    return check_digit