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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 Hash(self):
 """ Get the hash of the transaction. Returns: UInt256: """

        if not self.__hash:
            ba = bytearray(binascii.unhexlify(self.GetHashData()))
            hash = Crypto.Hash256(ba)
            self.__hash = UInt256(data=hash)
        return self.__hash