_getOrCreateSheetViewNode() {
        let sheetViewsNode = xmlq.findChild(this._node, "sheetViews");
        if (!sheetViewsNode) {
            sheetViewsNode = {
                name: "sheetViews",
                attributes: {},
                children: [{
                    name: "sheetView",
                    attributes: {
                        workbookViewId: 0
                    },
                    children: []
                }]
            };

            xmlq.insertInOrder(this._node, sheetViewsNode, nodeOrder);
        }

        return xmlq.findChild(sheetViewsNode, "sheetView");
    }
Get the sheet view node if it exists or create it if it doesn't.
@returns {{}} The sheet view node.
@private