{
  "manageEntity": {
    "action": "Save",
    "entityId": "644891",
    "entityType": "Track",
    "nonce": "0x2af4e9a29053b3dccc8abaaf566988805509b516f09acd82fd7e3017b58f494c",
    "signature": "0x3124ac36633aee1f70384320e23bf41a24df3cedea1476af4aa1b7609626fe2e4d3cd785a0363e347feb369d45a2aca74e30a4e8faeed3e8b9b54173f5d56c291c",
    "signer": "0xD24271e3B8CCFB603860EA392E94eD5AE2538703",
    "userId": "456716469"
  }
}