How to use the @ethersproject/strings.toUtf8String function in @ethersproject/strings

return 1;
        }
        return 0;
    }
    // Load all the words
    for (var length_1 = 3; length_1 <= 9; length_1++) {
        var d = data[length_1 - 3];
        for (var offset = 0; offset < d.length; offset += length_1) {
            var word = [];
            for (var i = 0; i < length_1; i++) {
                var k = mapping.indexOf(d[offset + i]);
                word.push(227);
                word.push((k & 0x40) ? 130 : 129);
                word.push((k & 0x3f) + 128);
            }
            wordlist.push(strings_1.toUtf8String(word));
        }
    }
    wordlist.sort(sortJapanese);
    // For some reason kyoku and kiyoku are flipped in node (!!).
    // The order SHOULD be:
    //   - kyoku
    //   - kiyoku
    if (hex(wordlist[442]) === KiYoKu && hex(wordlist[443]) === KyoKu) {
        var tmp = wordlist[442];
        wordlist[442] = wordlist[443];
        wordlist[443] = tmp;
    }
    if (wordlist_1.Wordlist.check(lang) !== "0xcb36b09e6baa935787fd762ce65e80b0c6a8dabdfbc3a7f86ac0e2c4fd111600") {
        wordlist = null;
        throw new Error("BIP39 Wordlist for ja (Japanese) FAILED");
    }

// Acute accent
        if (c === 47) {
            output.push(204);
            output.push(129);
            // n-tilde
        }
        else if (c === 126) {
            output.push(110);
            output.push(204);
            output.push(131);
        }
        else {
            output.push(c);
        }
    });
    return toUtf8String(output);
}
function loadWords(lang) {

// Acute accent
        if (c === 47) {
            output.push(204);
            output.push(129);
            // n-tilde
        }
        else if (c === 126) {
            output.push(110);
            output.push(204);
            output.push(131);
        }
        else {
            output.push(c);
        }
    });
    return strings_1.toUtf8String(output);
}
function loadWords(lang) {

Array.prototype.forEach.call(toUtf8Bytes(word), (c) => {
        // Acute accent
        if (c === 47) {
            output.push(204);
            output.push(129);
            // Grave accent
        }
        else if (c === 45) {
            output.push(204);
            output.push(128);
        }
        else {
            output.push(c);
        }
    });
    return toUtf8String(output);
}
function loadWords(lang) {

function loadWords(lang) {
    if (wordlist !== null) {
        return;
    }
    wordlist = [];
    // Transforms for normalizing (sort is a not quite UTF-8)
    const transform = {};
    // Delete the diacritic marks
    transform[toUtf8String([227, 130, 154])] = false;
    transform[toUtf8String([227, 130, 153])] = false;
    // Some simple transforms that sort out most of the order
    transform[toUtf8String([227, 130, 133])] = toUtf8String([227, 130, 134]);
    transform[toUtf8String([227, 129, 163])] = toUtf8String([227, 129, 164]);
    transform[toUtf8String([227, 130, 131])] = toUtf8String([227, 130, 132]);
    transform[toUtf8String([227, 130, 135])] = toUtf8String([227, 130, 136]);
    // Normalize words using the transform
    function normalize(word) {
        let result = "";
        for (let i = 0; i < word.length; i++) {
            let kana = word[i];
            const target = transform[kana];
            if (target === false) {
                continue;
            }
            if (target) {
                kana = target;
            }
            result += kana;
        }

function dropDiacritic(word) {
    logger.checkNormalize();
    return toUtf8String(Array.prototype.filter.call(toUtf8Bytes(word.normalize("NFD").toLowerCase()), (c) => {
        return ((c >= 65 && c <= 90) || (c >= 97 && c <= 123));
    }));
}
function expand(word) {

function dropDiacritic(word) {
    wordlist_1.logger.checkNormalize();
    return strings_1.toUtf8String(Array.prototype.filter.call(strings_1.toUtf8Bytes(word.normalize("NFD").toLowerCase()), function (c) {
        return ((c >= 65 && c <= 90) || (c >= 97 && c <= 123));
    }));
}
function expand(word) {

function dropDiacritic(word: string): string {
    logger.checkNormalize();
    return toUtf8String(Array.prototype.filter.call(toUtf8Bytes(word.normalize("NFD").toLowerCase()), (c: number) => {
        return ((c >= 65 && c <= 90) || (c >= 97 && c <= 123));
    }));
}

function dropDiacritic(word) {
    logger.checkNormalize();
    return toUtf8String(Array.prototype.filter.call(toUtf8Bytes(word.normalize("NFD").toLowerCase()), (c) => {
        return ((c >= 65 && c <= 90) || (c >= 97 && c <= 123));
    }));
}
function expand(word) {