{
  "manageEntity": {
    "action": "Save",
    "entityId": "637450452",
    "entityType": "Track",
    "nonce": "0x444c777886367757d8c3d7e02a32d447a565c658f0f40b6a657f7c2d0b9e8bdc",
    "signature": "0x5d6bd7e842fb3ea96b2eb00af5e5f7368809962d84aa1d0f6eb644276a4537405800730d8985452316ec2f14bb4cc6ec9a55a4e984658532190d69350bea107e1c",
    "signer": "0x48FD75f1b7D81A96b8b8624aB7040523C402c202",
    "userId": "325172820"
  }
}