{
  "manageEntity": {
    "action": "Save",
    "entityId": "640804772",
    "entityType": "Track",
    "nonce": "0x884e00a631790dfd5f030f914ea58825ee0dd10c8874736e08bce8464428c71c",
    "signature": "0xfe0a1a2d51edfb1e480491f39568f9acdfd129429d45e654cd4c4757a95b9b915c5cfccdb081e8ea15f69464b14b161dc2f647dae19f3b15e8315bef19db6c461c",
    "signer": "0xbF4F1f4df4779768AfE75515b1552a2Bc5b4Dd32",
    "userId": "100976759"
  }
}