Ошибка при просмотре 404

<?php
 
/**
 * Returns months names for current language
 * @return array
 */
function lang_months() {
    return [
        'yanvar', 'fevral', 'mart', 'aprel', 'may', 'iyun',
        'iyul', 'avqust', 'sentyabr', 'oktyabr', 'noyabr', 'dekabr'
    ];
}
 
/**
 * Returns days names for current language
 * @return array
 */
function lang_days() {
    return [
        'b', 'be', '&ccedil;a', '&ccedil;', 'ca', 'c', 'ş'
    ];
}
 
/**
 * Returns date for current language
 * @param string $date_string
 * @return string
 */
function lang_date($date_string) {
    $eng_months = [
        'January', 'February', 'March', 'April', 'May', 'June',
        'July', 'August', 'September', 'October', 'November', 'December'
    ];
    return str_replace($eng_months, lang_months(), $date_string);
}
 
/**
 * Converts string from current language to SLUG
 * @param string $string Input string
 * @param boolean $disallow_numeric Disallow numeric SLUG
 * @return string
 */
function lang_slug(string $string, $disallow_numeric = true) {
    $string = mb_strtolower(strip_tags(trim($string)));
 
    $string = strtr($string, [
        // Азербайджанский алфавит
        'ə' => 'e', '&ccedil;' => 'ch', 'ğ' => 'gh', 'ı' => 'i', '&ouml;' => 'o',
        'ş' => 'sh', '&uuml;' => 'u',
        'Ə' => 'e', '&Ccedil;' => 'ch', 'Ğ' => 'gh', 'I' => 'i', '&Ouml;' => 'o',
        'Ş' => 'sh', '&Uuml;' => 'u',
 
        // Русский алфавит
        'а' => 'a', 'б' => 'b', 'в' => 'v', 'г' => 'g', 'д' => 'd', 'е' => 'e',
        'ё' => 'yo', 'ж' => 'zh', 'з' => 'z', 'и' => 'i', 'й' => 'i',
        'к' => 'k', 'л' => 'l', 'м' => 'm', 'н' => 'n', 'о' => 'o', 'п' => 'p',
        'р' => 'r', 'с' => 's', 'т' => 't', 'у' => 'u', 'ф' => 'f', 'х' => 'h',
        'ц' => 'c', 'ч' => 'ch', 'ш' => 'sh', 'щ' => 'sch', 'ъ' => '',
        'ы' => 'y', 'ь' => '', 'э' => 'e', 'ю' => 'yu', 'я' => 'ja'
    ]);
 
    $slug = preg_replace('/[^a-z0-9\-\/]+/u', '-', $string);
    $slug = preg_replace('/-+/', '-', $slug);
    $slug = preg_replace('/\/+/', '/', $slug);
    $slug = trim($slug, '-/');
 
    if (!$slug) {
        $slug = 'untitled';
    }
 
    if ($disallow_numeric && ctype_digit($slug)) {
        $slug .= strtolower(date('F'));
    }
 
    return $slug;
}
 
/**
 * Set locale information
 * @return mixed
 */
function lang_setlocale() {
    $locale = 'ru_RU.UTF-8';
 
    setlocale(LC_COLLATE, $locale);
    setlocale(LC_CTYPE, $locale);
    setlocale(LC_MONETARY, $locale);
    setlocale(LC_TIME, $locale);
    if (defined('LC_MESSAGES')) {
        setlocale(LC_MESSAGES, $locale);
    }
    setlocale(LC_NUMERIC, 'POSIX');
 
    return true;
}
 
/**
 * Locale name
 */
define('LC_LANGUAGE_TERRITORY', 'ru_RU');
 
/**
 * Locale validate regexp
 */
define('LC_LANGUAGE_VALIDATE_REGEXP', "/^([a-zа-яёйə&ouml;&uuml;ı&ccedil;şğ0-9 \.\?\@\,\-]*)$/ui");
 

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