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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_body_(cls):
 """Return JSON body of the datapoints. :return: JSON body of the datapoints. """

        json = []
        for series_name, data in six.iteritems(cls._datapoints):
            json.append({'name': series_name,
                         'columns': cls._fields,
                         'points': [[getattr(point, k) for k in cls._fields]
                                    for point in data]
                         })
        return json