{
  "manageEntity": {
    "action": "Save",
    "entityId": "421154",
    "entityType": "Track",
    "nonce": "0x59e420da9234de5b2f313109f1a44b2ec75ea36be86fa78e83787b94684a1347",
    "signature": "0x727e1fc45b29179de50ce2254cb5a0a1fb4aae92e2d9f8a790e8bc3a454de4d7728ddfc381ef4bf77e4bcbe7cadba26ff259e972c19030a81f3b534b8fbd26e51c",
    "signer": "0xA27B00F57fC7B3E81c4d7C4919aCec97E1fCf667",
    "userId": "329513359"
  }
}