def change_storage_class(self, new_storage_class, dst_bucket=None):
        if new_storage_class == 'STANDARD':
            return self.copy(self.bucket.name, self.name,
                             reduced_redundancy=False, preserve_acl=True)
        elif new_storage_class == 'REDUCED_REDUNDANCY':
            return self.copy(self.bucket.name, self.name,
                             reduced_redundancy=True, preserve_acl=True)
        else:
            raise BotoClientError('Invalid storage class: %s' %
                                  new_storage_class)
:param addr: An IPv6 address in presentation (string) format.
dataset/ETHPy150Open darcyliu/storyboard/boto/s3/key.py/Key.change_storage_class--crossover with--dataset/ETHPy150Open drkjam/netaddr/netaddr/strategy/ipv6.py/valid_str