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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):
 """ Convert the existing track to a JSON representation. """

        viewconf = json.loads(json.dumps(self.viewconf))

        for track in self.tracks:
            if track.position is None:
                raise ValueError(
                    "Track has no position: {}".format(track.viewconf["type"])
                )
            viewconf["tracks"][track.position] += [track.to_dict()]

        return viewconf