@classmethod
def from_pycbc(cls, fs, copy=True):
    """Convert a `pycbc.types.frequencyseries.FrequencySeries` into
        a `FrequencySeries`

        Parameters
        ----------
        fs : `pycbc.types.frequencyseries.FrequencySeries`
            the input PyCBC `~pycbc.types.frequencyseries.FrequencySeries`
            array

        copy : `bool`, optional, default: `True`
            if `True`, copy these data to a new array

        Returns
        -------
        spectrum : `FrequencySeries`
            a GWpy version of the input frequency series
        """
    return cls(fs.data, f0=0, df=fs.delta_f, epoch=fs.epoch, copy=copy)
