def get_results(self):
        """Return a formatted string for a tikz pgf-pie chart."""
        pie = ""
        for answer, cardinality in list(self.cardinality.items()):
            if not answer:
                ans = _("Left blank")
            ans = Question2Tex.get_clean_answer(answer)
            pie += f"{cardinality}/{ans},"
        if not pie:
            return ""
        final_answers = []
        for answer in pie.split(","):
            if answer:
                final_answers.append(answer)
        return "            {}".format(",\n            ".join(final_answers))