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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 items(self):
 """Return the set of items from the ResultSet. :return: List of tuples, (key, generator) """

        items = []
        for series in self._get_series():
            series_key = (series.get('measurement',
                                     series.get('name', 'results')),
                          series.get('tags', None))
            items.append(
                (series_key, self._get_points_for_series(series))
            )
        return items