How to use the @nivo/sankey.SankeyDefaultProps.colors function in @nivo/sankey

defaultValue: defaults.sort,
        controlType: 'choices',
        group: 'Base',
        controlOptions: {
            choices: ['auto', 'input', 'ascending', 'descending'].map(key => ({
                label: key,
                value: key,
            })),
        },
    },
    {
        key: 'colors',
        help: 'Defines how to compute nodes color.',
        type: 'string | Function | string[]',
        required: false,
        defaultValue: defaults.colors,
        controlType: 'ordinalColors',
        group: 'Base',
    },
    {
        key: 'width',
        enableControlForFlavors: ['api'],
        description: `
            not required if using
            \`\`.
        `,
        help: 'Chart width.',
        type: 'number',
        required: true,
        controlType: 'range',
        group: 'Base',
        controlOptions: {