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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 targetHi(self):
 """Return the high byte of the target message property. Used in All-Link Cleanup message types. """

        hi_byte = None
        if self.target.addr is not None and self._messageFlags.isBroadcast:
            hi_byte = self.target.bytes[2]
        return hi_byte