REST create a group with a parent

Hi there,

I'm trying to create a group with a parent. Here's my request:

{
    "name": "Group Name",
    "parent-groups": {
        "group": [
            { "key": "PARENT_GROUP" }
        ]
    }
}

I'm getting the following error:

Error has occurred during request processing (Bad Request).
Error: jetbrains.buildServer.server.rest.errors.BadRequestException: Only 'key', 'name' and 'description' attributes are supported when creating user groups.
Invalid request. Please check the request URL and data are correct.

Is it possible to do this via REST? Using TeamCity 9.0.4.