Fatal error: Uncaught Error: Call to undefined function trailingslashit() in /home/koochem1/public_html/wp-includes/class-wp-textdomain-registry.php:103 Stack trace: #0 /home/koochem1/public_html/wp-includes/l10n.php(784): WP_Textdomain_Registry->set('default', 'fa_IR', '/home/koochem1/...') #1 /home/koochem1/public_html/wp-includes/load.php(1401): load_textdomain('default', '/home/koochem1/...', 'fa_IR') #2 /home/koochem1/public_html/wp-includes/load.php(278): wp_load_translations_early() #3 /home/koochem1/public_html/wp-settings.php(74): wp_maintenance() #4 /home/koochem1/public_html/wp-config.php(82): require_once('/home/koochem1/...') #5 /home/koochem1/public_html/wp-load.php(50): require_once('/home/koochem1/...') #6 /home/koochem1/public_html/wp-blog-header.php(13): require_once('/home/koochem1/...') #7 /home/koochem1/public_html/index.php(17): require('/home/koochem1/...') #8 {main} thrown in /home/koochem1/public_html/wp-includes/class-wp-textdomain-registry.php on line 103