{
  "manageEntity": {
    "action": "Save",
    "entityId": "645904",
    "entityType": "Track",
    "nonce": "0x6a85f50cd32f8c3490483ae09432f58e97cb1dc7e8225cbc9af2d7214d4a1171",
    "signature": "0xe888ccc4f7464a21c98481acfe9e4a35b75c0a9561384f4803186357fb8c402d0b5edf9d93e0f571e9f72eabb20d9d7a8df6f759ac6b3c6e085b5d76aaf503b51b",
    "signer": "0x4fdc03E53311BF6b1B8728dd0Ae0630bF74176f1",
    "userId": "162770660"
  }
}