{
    "Element Sets": [
        {
            "index": 0,
            "attribute": "air"
        }
    ],
    "Face Sets": [
        {
            "index": 0,
            "boundary": "PEC"
        },
        {
            "index": 1,
            "boundary": "ABC"
        }
    ],
    "Hybrid Mesh": {
        "enable": true,
        "holes": [[0.0, 0.0, 0.0]]
    }
}