Relevanssi remove_punct to retain ampersands

function your_relevanssi_remove_punct($a) {
    $a = strip_tags($a);
    $a = stripslashes($a);
    $a = str_replace('’', '', $a);
    $a = str_replace("'", '', $a);
    $a = str_replace("´", '', $a);
    $a = str_replace("’", '', $a);
    $a = str_replace("‘", '', $a);
    $a = str_replace("„", '', $a);
    $a = str_replace("·", '', $a);
    $a = str_replace("”", '', $a);
    $a = str_replace("“", '', $a);
    $a = str_replace("…", '', $a);
    $a = str_replace("€", '', $a);
    $a = str_replace("­", '', $a);
    $a = str_replace("—", ' ', $a);
    $a = str_replace("–", ' ', $a);
    $a = str_replace("×", ' ', $a);
    $a = str_replace('&', 'AMPERSANDHERE', $a);
        $a = preg_replace('/[[:punct:]]+/u', ' ', $a);
    $a = str_replace('AMPERSANDHERE', '&', $a);
        $a = preg_replace('/[[:space:]]+/', ' ', $a);
    $a = trim($a);
        return $a;
}