{
  "manageEntity": {
    "action": "Save",
    "entityId": "1521620153",
    "entityType": "Track",
    "nonce": "1787954482251290484",
    "signature": "0x0cafc8bcc64339fb9c1f0bbed4809ba5ce693365ee5fbc69fe76a689e9ecc66c50d2f7f031efd8410fe979dada3adcfc5b57e0306b464bc10847a4e2425a635c1c",
    "signer": "0x6620103988B969bE5810F1B5530c1A44Fe6048A1",
    "userId": "568518925"
  }
}