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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 a dictionary representation of the Predicate."""

        return {
            'predicate': self.predicate,
            'parents': list(self.supertypes),
            'synopses': [[role.to_dict() for role in synopsis]
                         for synopsis in self.synopses]
        }