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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 _to_dict(self):
 """Return keyset's state as a dict. The result can be used to serialize the instance and reconstitute it later using :meth:`_from_dict`. :rtype: dict :returns: state of this instance. """

        if self.all_:
            return {"all": True}

        return {
            "keys": self.keys,
            "ranges": [keyrange._to_dict() for keyrange in self.ranges],
        }