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Fatal error: Uncaught TypeError: Init::get_conn(): Return value must be of type mysqli, bool returned in /www/wwwroot/php-project/iapp-doc-master/include/init.php:16 Stack trace: #0 /www/wwwroot/php-project/iapp-doc-master/include/init.php(61): Init::get_conn() #1 /www/wwwroot/php-project/iapp-doc-master/article.php(3): require('...') #2 {main} thrown in /www/wwwroot/php-project/iapp-doc-master/include/init.php on line 16