{
  "nodes": [
    "queued",
    "approved",
    "sent"
  ],
  "start": "queued",
  "goal": "sent",
  "edges": [
    {
      "from": "queued",
      "to": "approved",
      "allowed": false
    },
    {
      "from": "approved",
      "to": "sent",
      "allowed": true
    }
  ]
}