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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 _Ep(self):
 """ Proton energy array in GeV """

        return np.logspace(
            np.log10(self.Epmin.to("GeV").value),
            np.log10(self.Epmax.to("GeV").value),
            int(self.nEpd * (np.log10(self.Epmax / self.Epmin))),
        )