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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 decode(self,data):
 """Decode the MAC address from a byte array. This will take the first 6 bytes from data and transform them into a MAC address string representation. This will be assigned to the attribute "val". It then returns the data stream minus the bytes consumed :param data: The data stream containing the value to decode at its head :type data: bytes :returns: The datastream minus the bytes consumed :rtype: bytes """

        self.val=':'.join("%02x" % x for x in reversed(data[:6]))
        return data[6:]