{
  "manageEntity": {
    "action": "Save",
    "entityId": "307721",
    "entityType": "Track",
    "nonce": "0x16bba71bbb86b630426eea1448d1eaefc380cf3430503ddffaa4cda3d4b1badb",
    "signature": "0xf00ab77f888c9e91dab850b0bf2b59e03004a4d41f1e16b4f451dcfd11647c9173d40fdf60cc9f9932895d86ae31eeb1a5955375cbfebe4ae0fd3d88fbe4e0c31b",
    "signer": "0xA27B00F57fC7B3E81c4d7C4919aCec97E1fCf667",
    "userId": "329513359"
  }
}