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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 smooth(polylines):
 """ smooth every polyline using spline interpolation """

    for c in polylines:
        if len(c) < 9:
            # smoothing wouldn't make sense here
            continue
        x = c[:, 0]
        y = c[:, 1]

        t = np.arange(x.shape[0], dtype=float)
        t /= t[-1]
        x = UnivariateSpline(t, x)(t)
        y = UnivariateSpline(t, y)(t)
        c[:, 0] = x
        c[:, 1] = y