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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 GetMacAddresses(self):
 """MAC addresses from all interfaces."""

    result = set()
    for interface in self.interfaces:
      if (interface.mac_address and
          interface.mac_address != b"\x00" * len(interface.mac_address)):
        result.add(Text(interface.mac_address.human_readable_address))
    return sorted(result)