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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 add_frequencyseries(self, spectrum, dB=True, power=False, **kwargs):
 """Plot the magnitude and phase of a complex-valued `FrequencySeries` Parameters spectrum : `~gwpy.frequencyseries.FrequencySeries` the (complex-valued) `FrequencySeries` to display db : `bool`, optional, default: `True` if `True`, display magnitude in decibels, otherwise display amplitude. power : `bool`, optional, default: `False` give `True` to incidate that ``spectrum`` holds power values, so ``dB = 10 * log(abs(spectrum))``, otherwise ``db = 20 * log(abs(spectrum))``. This argument is ignored if ``db=False``. **kwargs any other keyword arguments accepted by :meth:`~matplotlib.axes.Axes.plot` Returns ------- mag, phase : `tuple` of `lines <matplotlib.lines.Line2D>` the lines drawn for the magnitude and phase of the filter. """

        # parse spectrum arguments
        kwargs.setdefault('label', spectrum.name)
        # get magnitude
        mag = numpy.absolute(spectrum.value)
        if dB:
            mag = to_db(mag)
            if not power:
                mag *= 2.
        # get phase
        phase = numpy.angle(spectrum.value, deg=True)
        # plot
        w = spectrum.frequencies.value
        mline = self.maxes.plot(w, mag, **kwargs)[0]
        pline = self.paxes.plot(w, phase, **kwargs)[0]
        return mline, pline