{
  "manageEntity": {
    "action": "Save",
    "entityId": "490742730",
    "entityType": "Track",
    "nonce": "0xf25b740d54f4a3b03f4d15f2e5a8c52d4573e0280743528453c98ec97f5594e6",
    "signature": "0xa877be6189d8631050df378a24fa582c13e7d5964beb91fd8411eb530a8446617ce21a1760b6a413f4b8f9153c534a1a111841ec245b2b249c384b58f4e977e61c",
    "signer": "0x5D012C880480A2E1ab4345f6F374CFf73e040331",
    "userId": "10449019"
  }
}