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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_polarizations(h_plus, h_cross, remove_start_phase=True):
 """Return gravitational wave phase Return the gravitation-wave phase from the h_plus and h_cross polarizations of the waveform. The returned phase is always positive and increasing with an initial phase of 0. Parameters h_plus : TimeSeries An PyCBC TmeSeries vector that contains the plus polarization of the gravitational waveform. h_cross : TimeSeries A PyCBC TmeSeries vector that contains the cross polarization of the gravitational waveform. Returns ------- GWPhase : TimeSeries A TimeSeries containing the gravitational wave phase. Examples --------s f_lower=30, delta_t=1.0/4096) """

    p = numpy.unwrap(numpy.arctan2(h_cross.data, h_plus.data)).astype(
        real_same_precision_as(h_plus))
    if remove_start_phase:
        p += -p[0]
    return TimeSeries(p, delta_t=h_plus.delta_t, epoch=h_plus.start_time,
        copy=False)