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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 _scale_enum(anchor, scales):
 """ Enumerate a set of anchors for each scale wrt an anchor. """

        w, h, x_ctr, y_ctr = AnchorGenerator._whctrs(anchor)
        ws = w * scales
        hs = h * scales
        anchors = AnchorGenerator._mkanchors(ws, hs, x_ctr, y_ctr)
        return anchors