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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 _feature_most_population(self, results):
 """ Find the placename with the largest population and return its country. More population is a rough measure of importance. Paramaters results: dict output of `query_geonames` Returns ------- most_pop: str ISO code of country of place with largest population, or empty string if none """


        try:
            populations = [i['population'] for i in results['hits']['hits']]
            most_pop = results['hits']['hits'][np.array(populations).astype("int").argmax()]
            return most_pop['country_code3']
        except Exception as e:
            return ""