NewsletterTemplateCreateBody

{
    "collaboration": {
        "editorIds": [
            0
        ],
        "ownerIds": [
            0
        ],
        "type": "PRIVATE"
    },
    "description": "string",
    "name": "string",
    "template": {
        "brandId": 0,
        "description": "string",
        "items": [
            {
                "fields": {
                    "count": 0,
                    "dateRangeType": "TODAY",
                    "labelIds": [
                        0
                    ],
                    "order": "MANUAL",
                    "orderArray": [
                        "string"
                    ]
                },
                "note": "string",
                "order": 0,
                "title": "string",
                "type": "HEADING"
            }
        ],
        "name": "string"
    },
    "type": "NEWSLETTER"
}