def csv(self):
        csv_string = StringIO()
        header = ",".join(self.ranked_names) + "\n"
        csv_string.write(header)
        writer = csv.writer(csv_string, lineterminator="\n")
        for irep in range(self.nrepetitions):
            data = [self.normalised_scores[rank][irep]
                    for rank in self.ranking]
            writer.writerow(list(map(str, data)))
        return csv_string.getvalue()
Returns:
dataset/ETHPy150Open Axelrod-Python/Axelrod/axelrod/result_set.py/ResultSet.csv