{
  "manageEntity": {
    "action": "Save",
    "entityId": "645599513",
    "entityType": "Track",
    "nonce": "1788047174987941554",
    "signature": "0xe606397a1834b640eb030e5c9e2b2a79f52561ea52bc2840fb663c5f81a6888b139c3fe1cd5fdee8b0c54714ecf2daa678985c25a87cd85c7fc04dcae0ccacf51c",
    "signer": "0xd30fAF377491796757Ef4C1B0ccA8a407920e663",
    "userId": "451691735"
  }
}