def _applySpecial_MeshOpts_vertexSet(args, overlayList, displayCtx, target):
    """Applies the :attr:`.MeshOpts.vertexSet` option. """
    import fsleyes.actions.loadvertexdata as loadvertexdata
    last = len(args.vertexSet) - 1
    for i, vd in enumerate(args.vertexSet):
        loadvertexdata.loadVertices(target.overlay, displayCtx, vd, select=
            i == last)
