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Warning: include_once(): Failed opening 'Mage/Core/function.php' for inclusion (include_path='/home/exhibepo/public_html/app/code/local:/home/exhibepo/public_html/app/code/comunity:/home/exhibepo/public_html/app/code/core:/home/exhibepo/public_html/lib:.:/usr/local/php56/pear') in /home/exhibepo/public_html/app/Mage.php on line 50

Fatal error: Call to undefined function is_dir_writeable() in /home/exhibepo/public_html/app/code/core/Mage/Core/Model/Config/Options.php on line 220