<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _json_body_(cls):
 """Return the JSON body of given datapoints. :return: JSON body of these datapoints. """

        json = []
        for series_name, data in six.iteritems(cls._datapoints):
            for point in data:
                json_point = {
                    "measurement": series_name,
                    "fields": {},
                    "tags": {},
                    "time": getattr(point, "time")
                }

                for field in cls._fields:
                    value = getattr(point, field)
                    if value is not None:
                        json_point['fields'][field] = value

                for tag in cls._tags:
                    json_point['tags'][tag] = getattr(point, tag)

                json.append(json_point)
        return json