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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 json(self):
 """ json representation of the metadata. :return: json representation of the metadata :rtype: str """

        json_dumps = json.dumps(
            self.dict,
            indent=2,
            sort_keys=True,
            separators=(',', ': '),
            cls=MetadataEncoder
        )
        if not json_dumps.endswith('\n'):
            json_dumps += '\n'
        return json_dumps