{
  "manageEntity": {
    "action": "Save",
    "entityId": "666497",
    "entityType": "Track",
    "nonce": "0x7872ee176c8235998472c1b0f0bf51385d5abdbdac2054218e8231def60fa44d",
    "signature": "0x2c75dee35638d560a3644ae2763f157dcad4d4cb10cb0480fc7a1a91a87aecc133bf8cb3ccb43566a87e875fa82925f8d1e77dbde3a0f81a5cf674a17c7a99f21b",
    "signer": "0x44BAdCFCf42113CbB67f519e4efa576B336f9bf7",
    "userId": "136844578"
  }
}