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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 folding_model_gradient(rvec, rcut):
 r"""computes the potential's gradient at point rvec"""

    rnorm = np.linalg.norm(rvec)
    if rnorm == 0.0:
        return np.zeros(rvec.shape)
    r = rnorm - rcut
    if r < 0.0:
        return -5.0 * r * rvec / rnorm
    return (1.5 * r - 2.0) * rvec / rnorm