{
  "manageEntity": {
    "action": "Save",
    "entityId": "391128",
    "entityType": "Track",
    "nonce": "0x74d645c6aeba16eb85fe97d973288224aa6b80ca0d86a26980554a92f9309ebc",
    "signature": "0x48de84ef62798a53b79da9f4b7f4ba45e63bc1918cc00de2a17d6f0fd717262c4642912be018a4e420e51775db63628dcc33aa992bdd2a7df57024998cc80d5b1c",
    "signer": "0x48FD75f1b7D81A96b8b8624aB7040523C402c202",
    "userId": "325172820"
  }
}