How to use the @nivo/bar.BarDefaultProps.layout function in @nivo/bar

defaultValue: defaults.groupMode,
        controlType: 'radio',
        group: 'Base',
        controlOptions: {
            choices: [
                { label: 'stacked', value: 'stacked' },
                { label: 'grouped', value: 'grouped' },
            ],
        },
    },
    {
        key: 'layout',
        help: `How to display bars.`,
        type: 'string',
        required: false,
        defaultValue: defaults.layout,
        controlType: 'radio',
        group: 'Base',
        controlOptions: {
            choices: [
                { label: 'horizontal', value: 'horizontal' },
                { label: 'vertical', value: 'vertical' },
            ],
        },
    },
    {
        key: 'reverse',
        help:
            'Reverse bars, starts on top instead of bottom for vertical layout and right instead of left for horizontal one.',
        type: 'boolean',
        required: false,
        defaultValue: defaults.reverse,