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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 run_stats_df(self):
 """Returns self.run_stats over search params as pandas dataframe."""


        run_stats_df = []
        for x in self.run_stats:
            search_results = {**x["search_params"]}
            search_results["score"] = x["score"]
            run_stats_df.append(search_results)
        return pd.DataFrame(run_stats_df)