Fatal error: Uncaught Error: Class 'block_base' not found in /home/junior47895/public_html/aulavirtual/AulaVirtual_22Apr/blocks/navigation/block_navigation.php:37 Stack trace: #0 {main} thrown in /home/junior47895/public_html/aulavirtual/AulaVirtual_22Apr/blocks/navigation/block_navigation.php on line 37