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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 _router_address(self, data):
 """only for IPv6 addresses"""

        args = data.split()[1:]
        try:
            self._relay_attrs['ip_v6'].extend(args)
        except KeyError:
            self._relay_attrs['ip_v6'] = list(args)