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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 restore_checkpoint(filename):
 """Resumes the simulation from a previous saved point."""

        with gzip.open(filename) as f:
            generation, config, population, species_set, rndstate = pickle.load(f)
            random.setstate(rndstate)
            return Population(config, (population, species_set, generation))