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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 cut_spectrum(sp, l0, lf):
 """ Cuts spectrum given a wavelength interval, leaving origina intact Args: sp: Spectrum instance l0: initial wavelength lf: final wavelength Returns: Spectrum: cut spectrum """


    if l0 >= lf:
        raise ValueError("l0 must be lower than lf")
    idx0 = np.argmin(np.abs(sp.x - l0))
    idx1 = np.argmin(np.abs(sp.x - lf))
    out = copy.deepcopy(sp)
    out.x = out.x[idx0:idx1]
    out.y = out.y[idx0:idx1]
    return out