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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 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)