Creates a new variant set

{
  "type": "object",
  "required": [
    "body",
    "title"
  ],
  "properties": {
    "body": {
      "type": "string",
      "description": "Article content"
    },
    "category": {
      "type": "string"
    },
    "category_id": {
      "type": "integer"
    },
    "id": {
      "type": "integer",
      "description": "The unique identifier of a variant set"
    },
    "pub_date": {
      "type": "string",
      "format": "date-time"
    },
    "title": {
      "type": "string",
      "description": "Article title"
    }
  }
}