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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 peak_energy(self):
 """ Returns the peak energy in the nuFnu spectrum :return: peak energy in keV """


        # Eq. 6 in Massaro et al. 2004
        # (http://adsabs.harvard.edu/abs/2004A%26A...413..489M)

        return self.piv.value * pow(10, ((2 + self.alpha.value) * np.log(10)) / (2 * self.beta.value))