{
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      "author": "Stefania Overman",
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    "blockHash": "sha256 hex of canonicalJson({entry, formatVersion, index, previousHash, timestamp})",
    "signature": "Ed25519, base64, over canonicalJson({entry, index, previousHash}) where entry omits its signature field",
    "keyId": "first 16 hex chars of sha256 of publicKeyHex as utf8 text",
    "contentHash": "sha256 hex of the utf8 content text (articles, comments)",
    "statementHash": "sha256 hex of the utf8 statement text (document seals)",
    "documentHash": "sha256 hex of the raw document bytes (document seals)"
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}