function romatohiragana(t: text) :: text:
    replace all "ka" with "か" in {_t}
    replace all "ki" with "き" in {_t}
    replace all "ku" with "く" in {_t}
    replace all "ke" with "け" in {_t}
    replace all "ko" with "こ" in {_t}
    replace all "sa" with "さ" in {_t}
    replace all "si" with "し" in {_t}
    replace all "su" with "す" in {_t}
    replace all "se" with "せ" in {_t}
    replace all "so" with "そ" in {_t}
    replace all "ta" with "た" in {_t}
    replace all "ti" with "ち" in {_t}
    replace all "tu" with "つ" in {_t}
    replace all "te" with "て" in {_t}
    replace all "to" with "と" in {_t}
    replace all "na" with "な" in {_t}
    replace all "ni" with "に" in {_t}
    replace all "nu" with "ぬ" in {_t}
    replace all "ne" with "ね" in {_t}
    replace all "no" with "の" in {_t}
    replace all "ha" with "は" in {_t}
    replace all "hi" with "ひ" in {_t}
    replace all "hu" with "ふ" in {_t}
    replace all "he" with "へ" in {_t}
    replace all "ho" with "ほ" in {_t}
    replace all "ma" with "ま" in {_t}
    replace all "mi" with "み" in {_t}
    replace all "mu" with "む" in {_t}
    replace all "me" with "め" in {_t}
    replace all "mo" with "も" in {_t}
    replace all "ya" with "や" in {_t}
    replace all "yi" with "い" in {_t}
    replace all "yu" with "ゆ" in {_t}
    replace all "ye" with "いぇ" in {_t}
    replace all "yo" with "よ" in {_t}
    replace all "ra" with "ら" in {_t}
    replace all "ri" with "り" in {_t}
    replace all "ru" with "る" in {_t}
    replace all "re" with "れ" in {_t}
    replace all "ro" with "ろ" in {_t}
    replace all "wa" with "わ" in {_t}
    replace all "wi" with "うぃ" in {_t}
    replace all "we" with "うぇ" in {_t}
    replace all "wo" with "を" in {_t}
    replace all "nn" with "ん" in {_t}
    replace all "xa" with "ぁ" in {_t}
    replace all "xi" with "ぃ" in {_t}
    replace all "xu" with "ぅ" in {_t}
    replace all "xe" with "ぇ" in {_t}
    replace all "xo" with "ぉ" in {_t}
    replace all "xya" with "ゃ" in {_t}
    replace all "xyu" with "ゅ" in {_t}
    replace all "ょ" with "ょ" in {_t}
    replace all "xtu" with "っ" in {_t}
    replace all "xwa" with "ゎ" in {_t}
    replace all "ga" with "が" in {_t}
    replace all "gi" with "ぎ" in {_t}
    replace all "gu" with "ぐ" in {_t}
    replace all "ge" with "げ" in {_t}
    replace all "go" with "ご" in {_t}
    replace all "za" with "ざ" in {_t}
    replace all "zi" with "じ" in {_t}
    replace all "zu" with "ず" in {_t}
    replace all "ze" with "ぜ" in {_t}
    replace all "zo" with "ぞ" in {_t}
    replace all "da" with "だ" in {_t}
    replace all "di" with "ぢ" in {_t}
    replace all "du" with "づ" in {_t}
    replace all "de" with "で" in {_t}
    replace all "do" with "ど" in {_t}
    replace all "ba" with "ば" in {_t}
    replace all "bi" with "び" in {_t}
    replace all "bu" with "ぶ" in {_t}
    replace all "be" with "べ" in {_t}
    replace all "bo" with "ぼ" in {_t}
    replace all "pa" with "ぱ" in {_t}
    replace all "pi" with "ぴ" in {_t}
    replace all "pu" with "ぷ" in {_t}
    replace all "pe" with "ぺ" in {_t}
    replace all "po" with "ぽ" in {_t}
    replace all "wha" with "うぁ" in {_t}
    replace all "wi" with "うぃ" in {_t}
    replace all "we" with "うぇ" in {_t}
    replace all "who" with "うぉ" in {_t}
    replace all "va" with "ヴぁ" in {_t}
    replace all "vi" with "ヴぃ" in {_t}
    replace all "vu" with "ヴ" in {_t}
    replace all "ve" with "ヴぇ" in {_t}
    replace all "vo" with "ヴぉ" in {_t}
    replace all "kya" with "きゃ" in {_t}
    replace all "kyi" with "きぃ" in {_t}
    replace all "kyu" with "きゅ" in {_t}
    replace all "kye" with "きぇ" in {_t}
    replace all "kyo" with "きょ" in {_t}
    replace all "gya" with "ぎゃ" in {_t}
    replace all "gyi" with "ぎぃ" in {_t}
    replace all "gyu" with "ぎゅ" in {_t}
    replace all "gye" with "ぎぇ" in {_t}
    replace all "gyo" with "ぎょ" in {_t}
    replace all "sha" with "しゃ" in {_t}
    replace all "syi" with "しぃ" in {_t}
    replace all "shu" with "しゅ" in {_t}
    replace all "she" with "しぇ" in {_t}
    replace all "sho" with "しょ" in {_t}
    replace all "ja" with "じゃ" in {_t}
    replace all "zyi" with "じぃ" in {_t}
    replace all "ju" with "じゅ" in {_t}
    replace all "je" with "じぇ" in {_t}
    replace all "jo" with "じょ" in {_t}
    replace all "cha" with "ちゃ" in {_t}
    replace all "chi" with "ち" in {_t}
    replace all "chu" with "ちゅ" in {_t}
    replace all "che" with "ちぇ" in {_t}
    replace all "cho" with "ちょ" in {_t}
    replace all "dya" with "ぢゃ" in {_t}
    replace all "dyi" with "ぢぃ" in {_t}
    replace all "dyu" with "ぢゅ" in {_t}
    replace all "dye" with "ぢぇ" in {_t}
    replace all "dyo" with "ぢょ" in {_t}
    replace all "tha" with "てゃ" in {_t}
    replace all "thi" with "てぃ" in {_t}
    replace all "thu" with "てゅ" in {_t}
    replace all "the" with "てぇ" in {_t}
    replace all "tho" with "てょ" in {_t}
    replace all "dha" with "でゃ" in {_t}
    replace all "dhi" with "でぃ" in {_t}
    replace all "dhu" with "でゅ" in {_t}
    replace all "dhe" with "でぇ" in {_t}
    replace all "dho" with "でょ" in {_t}
    replace all "nya" with "にゃ" in {_t}
    replace all "nyi" with "にぃ" in {_t}
    replace all "nyu" with "にゅ" in {_t}
    replace all "nye" with "にぇ" in {_t}
    replace all "nyo" with "にょ" in {_t}
    replace all "hya" with "ひゃ" in {_t}
    replace all "hyi" with "ひぃ" in {_t}
    replace all "hyu" with "ひゅ" in {_t}
    replace all "hye" with "ひぇ" in {_t}
    replace all "hyo" with "ひょ" in {_t}
    replace all "bya" with "びゃ" in {_t}
    replace all "byi" with "びぃ" in {_t}
    replace all "byu" with "びゅ" in {_t}
    replace all "bye" with "びぇ" in {_t}
    replace all "byo" with "びょ" in {_t}
    replace all "pya" with "ぴゃ" in {_t}
    replace all "pyi" with "ぴぃ" in {_t}
    replace all "pyu" with "ぴゅ" in {_t}
    replace all "pye" with "ぴぇ" in {_t}
    replace all "pyo" with "ぴょ" in {_t}
    replace all "fa" with "ふぁ" in {_t}
    replace all "fi" with "ふぃ" in {_t}
    replace all "fu" with "ふ" in {_t}
    replace all "fe" with "ふぇ" in {_t}
    replace all "fo" with "ふぉ" in {_t}
    replace all "mya" with "みゃ" in {_t}
    replace all "myi" with "みぃ" in {_t}
    replace all "myu" with "みゅ" in {_t}
    replace all "mye" with "みぇ" in {_t}
    replace all "myo" with "みょ" in {_t}
    replace all "rya" with "りゃ" in {_t}
    replace all "ryi" with "りぃ" in {_t}
    replace all "ryu" with "りゅ" in {_t}
    replace all "rye" with "りぇ" in {_t}
    replace all "ryo" with "りょ" in {_t}
    replace all "a" with "あ" in {_t}
    replace all "i" with "い" in {_t}
    replace all "u" with "う" in {_t}
    replace all "e" with "え" in {_t}
    replace all "o" with "お" in {_t}
    return {_t}