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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_energy(rvec, rcut):
 r"""computes the potential energy at point rvec"""

    r = np.linalg.norm(rvec) - rcut
    rr = r ** 2
    if r < 0.0:
        return -2.5 * rr
    return 0.5 * (r - 2.0) * rr