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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 local_address(self):
 """ Local endpoint address as a tuple """

        if not self._local_address:
            self._local_address = self.proto.reader._transport.get_extra_info('sockname')
            if len(self._local_address) == 4:
                self._local_address = self._local_address[:2]
        return self._local_address