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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 _add_to(self, uuid, dest, other):
 """Add `item` to `dest` set, ensuring `item` is not present in `other` set."""

        _assert_uuid(uuid)
        try:
            other.remove(uuid)
        except KeyError:
            pass
        dest.add(uuid)