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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 spheres_sep(ar, aR, br, bR):
 """Return the separation distance between two spheres. Parameters ar, br: array-like, shape (n,) in n dimensions Coordinates of the centres of the spheres `a` and `b`. aR, bR: float Radiuses of the spheres `a` and `b`. Returns ------- d: float Separation distance. A negative value means the spheres intersect each other. """

    return vector.vector_mag(ar - br) - (aR + bR)