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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_json(self):
 """ Creates a JSON serializable representation of this instance Returns: :obj:`dict`: For example, { "lat": 9.3470298, "lon": 3.79274, "time": "2016-07-15T15:27:53.574110" } """

        return {
            'lat': self.lat,
            'lon': self.lon,
            'time': self.time.isoformat() if self.time is not None else None
        }