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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_hdf(self, filename, path='', overwrite=False):
 """ Saves PopulationSet to HDF file. """

        if os.path.exists(filename) and overwrite:
            os.remove(filename)

        for pop in self.poplist:
            name = pop.modelshort
            pop.save_hdf(filename, path='{}/{}'.format(path,name), append=True)