node.json

{
    "nodes": [
        {
            "id": "Alice"
        },
        {
            "id": "Bob"
        },
        {
            "id": "Carol"
        },
        {
            "id": "Carol"
        },
        {
            "id": "Carol"
        },
        {
            "id": "Carol"
        },
        {
            "id": "Carol"
        },
        {
            "id": "Carol"
        }
    ],
    "links": [
        {
            "source": 0,
            "target": 1
        },
        {
            "source": 1,
            "target": 2
        }
    ]
}