def unionstore(self, dest, *others, **kwargs):
        """
        Store the union of the current set and one or more
        others in a new key.

        :param dest: the name of the key to store union
        :param others: One or more :py:class:`ZSet` instances
        :returns: A :py:class:`ZSet` referencing ``dest``.
        """
        keys = [self.key]
        keys.extend([other.key for other in others])
        self.database.zunionstore(dest, keys, **kwargs)
        return self.database.ZSet(dest)
Store the union of the current set and one or more
        others in a new key.

        :param dest: the name of the key to store union
        :param others: One or more :py:class:`ZSet` instances
        :returns: A :py:class:`ZSet` referencing ``dest``.