{
  "manageEntity": {
    "action": "Save",
    "entityId": "4281",
    "entityType": "Playlist",
    "metadata": "{\"is_save_of_repost\":false}",
    "nonce": "0x75bd502fc2bd452ee50ddb1ff478a2be6e7a2864b989c86f164b61e728ed8fbb",
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    "signer": "0x3421B696Ad9D551F3118619583926F2ff9C11D42",
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}