function wp_maintenance_mode() {

if (!current_user_can(‘edit_themes’) || !is_user_logged_in()) {
wp_die(‘<h1>.</h1><br />’);
}
}
add_action(‘get_header’, ‘wp_maintenance_mode’);<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /www/doc/www.vysokyvrch.sk/www/wp-content/themes/et-agency/functions.php:1) in <b>/www/doc/www.vysokyvrch.sk/www/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1673</b><br />
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<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /www/doc/www.vysokyvrch.sk/www/wp-content/themes/et-agency/functions.php:1) in <b>/www/doc/www.vysokyvrch.sk/www/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1673</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /www/doc/www.vysokyvrch.sk/www/wp-content/themes/et-agency/functions.php:1) in <b>/www/doc/www.vysokyvrch.sk/www/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1673</b><br />
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<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /www/doc/www.vysokyvrch.sk/www/wp-content/themes/et-agency/functions.php:1) in <b>/www/doc/www.vysokyvrch.sk/www/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1673</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /www/doc/www.vysokyvrch.sk/www/wp-content/themes/et-agency/functions.php:1) in <b>/www/doc/www.vysokyvrch.sk/www/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1673</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /www/doc/www.vysokyvrch.sk/www/wp-content/themes/et-agency/functions.php:1) in <b>/www/doc/www.vysokyvrch.sk/www/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1673</b><br />
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<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /www/doc/www.vysokyvrch.sk/www/wp-content/themes/et-agency/functions.php:1) in <b>/www/doc/www.vysokyvrch.sk/www/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1673</b><br />
{"code":"rest_user_invalid_id","message":"Invalid user ID.","data":{"status":404}}