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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 pairwise_point_combinations(xs, ys, anchors):
 """ Does an in-place addition of the four points that can be composed by combining coordinates from the two lists to the given list of anchors """

    for i in xs:
        anchors.append((i, max(ys)))
        anchors.append((i, min(ys)))
    for i in ys:
        anchors.append((max(xs), i))
        anchors.append((min(xs), i))