How to Wrap Nested Arrays in Objects

export default {
	name: 'clusterItems',
	type: 'array',
	title: 'Cluster Items',
	of: [
		{
			type: 'image'
		},
		{
			type: 'video'
		},
		{
			type: 'textContent'
		}
	]
};

export default {
	name: 'cluster',
	type: 'object',
	title: 'Cluster',
	fields: [
		{
			name: 'items',
			type: 'clusterItems',
			title: 'Items'
		}
	]
};