{
  "manageEntity": {
    "action": "Save",
    "entityId": "550901",
    "entityType": "Track",
    "nonce": "0x0f9f1d6d9e4eded5ce75654e38992b6e701625509e91dc2295eb10ee2957b870",
    "signature": "0xbc73f100099a1054e54c0001dff95498a51853cce6aa46a951b314c224640d1c23f214b3e1c0cad428eb0fa0b690d47ec601cb02861ca54429f36dfdf07cf4851c",
    "signer": "0xA27B00F57fC7B3E81c4d7C4919aCec97E1fCf667",
    "userId": "329513359"
  }
}