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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 apply(self, byte, value, data, i, count):
 """ Apply mask, compare to expected value, shift and return result. Eventually, this could become a ``reduce`` function. :param byte: The byte to compare :param value: The currently accumulated value. :param data: The data buffer, (array of bytes). :param i: The position within the data buffer. :param count: The position of this comparison. :return: A new value with the bits merged in. :raises UnicodeDecodeError: if marked bits don't match. """

        if byte & self.mask == self.value:
            value <<= self.bits
            value |= byte & self.mask2
        else:
            raise UnicodeDecodeError(
                NAME, data, i, i + count, "invalid {}-byte sequence".format(self.count)
            )
        return value