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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 reflection_matrix(point, normal):
 """Return matrix to mirror at plane defined by point and normal vector. True True True """

    normal = unit_vector(normal[:3])
    M = np.identity(4)
    M[:3, :3] -= 2.0 * np.outer(normal, normal)
    M[:3, 3] = (2.0 * np.dot(point[:3], normal)) * normal
    return M