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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 Role."""

        d = {'rargname': self.rargname, 'value': self.value}
        if self.properties:
            d['properties'] = self.properties
        if self.optional:
            d['optional'] = self.optional
        return d