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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 psd(self, segment_duration, **kwds):
 """ Calculate the power spectral density of this time series. Use the `pycbc.psd.welch` method to estimate the psd of this time segment. For more complete options, please see that function. Parameters segment_duration: float Duration in seconds to use for each sample of the spectrum. kwds : keywords Additional keyword arguments are passed on to the `pycbc.psd.welch` method. Returns ------- psd : FrequencySeries Frequency series containing the estimated PSD. """

        from pycbc.psd import welch
        seg_len = int(segment_duration * self.sample_rate)
        seg_stride = int(seg_len / 2)
        return welch(self, seg_len=seg_len,
                           seg_stride=seg_stride,
                           **kwds)