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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 _update_noise(self, peak_num):
 """ Update live noise parameters """

        i = self.peak_inds_i[peak_num]
        self.noise_amp_recent = (0.875*self.noise_amp_recent
                                 + 0.125*self.sig_i[i])
        return