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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=''):
 """Save to .h5 file. """

        self.orbpop_long.save_hdf(filename,'{}/long'.format(path))
        self.orbpop_short.save_hdf(filename,'{}/short'.format(path))