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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 point_seg_sep(ar, br1, br2):
 """Return the minimum separation vector between a point and a line segment, in 3 dimensions. Parameters ar: array-like, shape (3,) Coordinates of a point. br1, br2: array-like, shape (3,) Coordinates for the points of a line segment Returns ------- sep: float array, shape (3,) Separation vector between point and line segment. """

    v = br2 - br1
    w = ar - br1

    c1 = np.dot(w, v)
    if c1 <= 0.0:
        return ar - br1

    c2 = np.sum(np.square(v))
    if c2 <= c1:
        return ar - br2

    b = c1 / c2
    bc = br1 + b * v
    return ar - bc