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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 save_info_df(self):
 """Saves the DataFrame with info about the runs to a JSON file"""

        logger.debug("running save_info_df")

        info_df = self.info_df
        top_level_dict = {'info_df': info_df, 'metadata': self._prm_packer()}

        # packing prms

        jason_string = json.dumps(top_level_dict,
                                  default=lambda info_df: json.loads(
                                      info_df.to_json()))
        with open(self.info_file, 'w') as outfile:
            outfile.write(jason_string)
        logger.info("Saved file to {}".format(self.info_file))