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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 union(self, other):
 """Return the union of sets as a new set. (i.e. all elements that are in either set.) Operates on either redish.types.Set or __builtins__.set. """

        if isinstance(other, self.__class__):
            return self.client.sunion([self.name, other.name])
        else:
            return self._as_set().union(other)