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Warning: include_once() [function.include]: Failed opening '/home/content/27/11981427/html/wp-admin/includes/class-wp-upgrader.php' for inclusion (include_path='.:/usr/local/php5_3/lib/php') in /home/content/27/11981427/html/wp-content/plugins/go_pricing/includes/core/class_plugin_upgrader.php on line 12

Fatal error: Class 'Plugin_Upgrader' not found in /home/content/27/11981427/html/wp-content/plugins/go_pricing/includes/core/class_plugin_upgrader.php on line 15