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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 truncate_transfer(transfer, ncorner=None):
 """Smoothly zero the edges of a frequency domain transfer function Parameters transfer : `numpy.ndarray` transfer function to start from, must have at least ten samples ncorner : `int`, optional number of extra samples to zero off at low frequency, default: `None` Returns ------- out : `numpy.ndarray` the smoothly truncated transfer function Notes ----- By default, the input transfer function will have five samples tapered off at the left and right boundaries. If `ncorner` is not `None`, then `ncorner` extra samples will be zeroed on the left as a hard highpass filter. See :func:`~gwpy.signal.window.planck` for more information. """

    nsamp = transfer.size
    ncorner = ncorner if ncorner else 0
    out = transfer.copy()
    out[0:ncorner] = 0
    out[ncorner:nsamp] *= planck(nsamp-ncorner, nleft=5, nright=5)
    return out