{
  "manageEntity": {
    "action": "Save",
    "entityId": "664240519",
    "entityType": "Track",
    "nonce": "0x817088e484c5e27d6559bf911e11980993f810e18cfeb673f06c781eddf263d9",
    "signature": "0x16a450a6c654643e961f5c0d78676435fabb3accd76d8207640381847bd6c2db42937f1207ccf752b3a58c31996976fe200bfbf4e1a40d533cf55982cc261c811c",
    "signer": "0xE7D37531a757aEaf8B2c8037a79C03819edc20Dc",
    "userId": "870684573"
  }
}