JED 1.6.0+ - Template world

{
    "config_version": {
        "id": "foo_bar_baz",
        "version": 1
    },
    "dimensions":
    [
        {
            "dim": 123,
            "world_template": "city_world",
            "dimensiontype": {
                "id": 123,
                "name": "City world",
                "keeploaded": false,
                "worldprovider": "WorldProviderSurfaceJED",
                "require_exact_match": true
            },
            "worldinfo_onetime": {
                "generatorName": "BIOMESOP",
                "RandomSeed": ""
            }
        }
    ]
}