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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 ifft(self):
 """Compute the one-dimensional discrete inverse Fourier transform of this `FrequencySeries`. Returns ------- out : :class:`~gwpy.timeseries.TimeSeries` the normalised, real-valued `TimeSeries`. See Also -------- :mod:`scipy.fftpack` for the definition of the DFT and conventions used. Notes ----- This method applies the necessary normalisation such that the condition holds: """

        from ..timeseries import TimeSeries
        nout = (self.size - 1) * 2
        # Undo normalization from TimeSeries.fft
        # The DC component does not have the factor of two applied
        # so we account for it here
        dift = npfft.irfft(self.value * nout) / 2
        new = TimeSeries(dift, epoch=self.epoch, channel=self.channel,
                         unit=self.unit, dx=1/self.dx/nout)
        return new