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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 best_unique_genomes(self, n):
 """Returns the most n fit genomes, with no duplication."""

        best_unique = {}
        for g in self.most_fit_genomes:
            best_unique[g.key] = g
        best_unique_list = list(best_unique.values())

        def key(genome):
            return genome.fitness

        return sorted(best_unique_list, key=key, reverse=True)[:n]