{
  "manageEntity": {
    "action": "Save",
    "entityId": "499123574",
    "entityType": "Track",
    "nonce": "0x1dd71fbec0dc13caf8fd39bc9481fec8f7ceeb873339787c627d07b9b9b27bcb",
    "signature": "0x0ddd673d98263edf9330ca7ee99f0bed17538fc5e0be6391afb972e307fb80ad5496b1b64bcbb57fe4255dce5348e27c6f7dd6445c62fc993f2921669031d0671c",
    "signer": "0x48FD75f1b7D81A96b8b8624aB7040523C402c202",
    "userId": "325172820"
  }
}