{
  "manageEntity": {
    "action": "Save",
    "entityId": "604573",
    "entityType": "Track",
    "nonce": "0x57e1931036d7da84bb01c0fe0492f3de7728db5d89677f5335c4bf1f287a59bd",
    "signature": "0x79573662065d908a7c7a28fbe541ff13a7341fc4c3bf5c1e73ecfa9f62fa55ce48a22b702b5e70355f8c0a2fdc785295cc3211b25bffe279059f86f60074bc9e1c",
    "signer": "0x243A439c272133AEEE0073AF4986dE391C430866",
    "userId": "77551267"
  }
}