[
 {
    "id" : 2,
    "child_ids" : [
      5,
      6
    ],
    "attributes": {
      "label" : "Node-2"
    }
 },
 {
    "id" : 5,
    "child_ids" : [],
    "attributes": {
      "label" : "Node-5"
    }
 },
 {
    "id" : 6,
    "child_ids" : [],
    "attributes": {
      "label" : "Node-6"
    }
 }
]