{
  "manageEntity": {
    "action": "Save",
    "entityId": "449476710",
    "entityType": "Track",
    "nonce": "0x907af3c4b68c34743977c1a484c3435df1b9bd9cd02920b338340a9fbfcebeea",
    "signature": "0x6b61cdfd3e3f252037249abea1f3044d42f63f2c5336afe4e2491da1542d622a02f5627f707dda85fb6eff283dfbbfba51fd140f1d45907dc037c3761e966d461b",
    "signer": "0x7061D02E53ede9391501fE7cc6aAEAec4059e8df",
    "userId": "618128736"
  }
}