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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 scale_to_vols(self, vols):
 """Scale ellipoids to a corresponding set of target volumes."""


        [self.ells[i].scale_to_vol(vols[i]) for i in range(self.nells)]
        self.vols = np.array(vols)
        self.expands = np.array([self.ells[i].expand
                                 for i in range(self.nells)])
        vol_tot = sum(vols)
        self.expand_tot *= vol_tot / self.vol_tot
        self.vol_tot = vol_tot