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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 iss_spi_divisor(self, sck):
 """ Calculate a USBISS SPI divisor value from the input SPI clock speed :param sck: SPI clock frequency :type sck: int :returns: ISS SCK divisor :rtype: int """

        _divisor = (6000000 / sck) - 1
        divisor = int(_divisor)

        if divisor != _divisor:
            raise ValueError('Non-integer SCK divisor.')

        if not 1 <= divisor < 256:
            error = (
                "The value of sck_divisor, {}, "
                "is not between 0 and 255".format(divisor)
            )
            raise ValueError(error)
        return divisor