code: function isKanaWithTrailingLatin(str) {
    REGEX_IS_KANA_WITH_TRAILING_LATIN = REGEX_IS_KANA_WITH_TRAILING_LATIN ||
      new RegExp('^' + '[' + R_KANA + ']+' + '[' + R_LATIN + ']' + '$');
    return REGEX_IS_KANA_WITH_TRAILING_LATIN.test(str);
  }
docs: Whether the string is exactly a sequence of Kana characters followed by one
  Latin character.
  
  @param {string} str
  @output {string}