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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 mac_addresses(self):
 """Return a list of mac addresses for this device. Computers don't tell you which network device is which. """

        mac_addresses = [self.findtext("general/mac_address")]
        if self.findtext("general/alt_mac_address"):
            mac_addresses.append(self.findtext("general/alt_mac_address"))
            return mac_addresses