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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 fit(self, volumes, energies):
 """ Fit energies as function of volumes. Args: volumes (list/np.array) energies (list/np.array) Returns: EOSBase: EOSBase object """

        eos_fit = self.model(np.array(volumes), np.array(energies))
        eos_fit.fit()
        return eos_fit