{
  "manageEntity": {
    "action": "Save",
    "entityId": "449940",
    "entityType": "Track",
    "nonce": "0x007cab0e3aecc1b41becbf410c8a9449785af21093a74fe491087757a1cec43c",
    "signature": "0x2d017f75342ee31006f59cc70cae2bb0259ed21b9c5a54c24505342b66ba4d7d0f00f36527d4cb870475388be111dad521937f355caf76441d7410a6bbd622571b",
    "signer": "0x40aE1C539711FBaE3930131b028D9c764fD8EaCb",
    "userId": "35251"
  }
}