{
  "manageEntity": {
    "action": "Save",
    "entityId": "449040297",
    "entityType": "Track",
    "nonce": "0x197b2bbcb4d316a337313fe8f6ee6718ec1577aa0170f60d99508292c7419314",
    "signature": "0xeedb32543cf85da846079ff495b2f2bbb3153e5905bd94bb280a468a8b68560038bbdad2741459f460139d69b7c319f765a93a3fde31a81d0fe1bac2343d37b81b",
    "signer": "0x5D012C880480A2E1ab4345f6F374CFf73e040331",
    "userId": "10449019"
  }
}