Warning: require_once(/var/www/magento/vendor/composer/autoload_real.php): Failed to open stream: No such file or directory in /var/www/magento/vendor/autoload.php on line 5

Fatal error: Uncaught Error: Failed opening required '/var/www/magento/vendor/composer/autoload_real.php' (include_path='.:/usr/share/pear:/usr/share/php') in /var/www/magento/vendor/autoload.php:5 Stack trace: #0 /var/www/magento/app/autoload.php(51): include() #1 /var/www/magento/app/bootstrap.php(44): require_once('...') #2 /var/www/magento/pub/index.php(46): require('...') #3 {main} thrown in /var/www/magento/vendor/autoload.php on line 5