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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 phase_from_frequencyseries(htilde, remove_start_phase=True):
 """Returns the phase from the given frequency-domain waveform. This assumes that the waveform has been sampled finely enough that the phase cannot change by more than pi radians between each step. Parameters htilde : FrequencySeries The waveform to get the phase for; must be a complex frequency series. remove_start_phase : {True, bool} Subtract the initial phase before returning. Returns ------- FrequencySeries The phase of the waveform as a function of frequency. """

    p = numpy.unwrap(numpy.angle(htilde.data)).astype(
            real_same_precision_as(htilde))
    if remove_start_phase:
        p += -p[0]
    return FrequencySeries(p, delta_f=htilde.delta_f, epoch=htilde.epoch,
        copy=False)