original_string: public function setup_file_system() {
          global $CFG;
          if ($this->filesystem === null) {
              require_once($CFG->libdir . '/filestorage/file_system.php');
              if (!empty($CFG->alternative_file_system_class)) {
                  $class = $CFG->alternative_file_system_class;
              } else {
                  // The default file_system is the filedir.
                  require_once($CFG->libdir . '/filestorage/file_system_filedir.php');
                  $class = file_system_filedir::class;
              }
              $this->filesystem = new $class();
          }
  
          return $this->filesystem;
      }
code: public function setup_file_system() {
          global $CFG;
          if ($this->filesystem === null) {
              require_once($CFG->libdir . '/filestorage/file_system.php');
              if (!empty($CFG->alternative_file_system_class)) {
                  $class = $CFG->alternative_file_system_class;
              } else {
                  // The default file_system is the filedir.
                  require_once($CFG->libdir . '/filestorage/file_system_filedir.php');
                  $class = file_system_filedir::class;
              }
              $this->filesystem = new $class();
          }
  
          return $this->filesystem;
      }
code_tokens: public function setup_file_system ( ) { global $ CFG ; if ( $ this -> filesystem === null ) { require_once ( $ CFG -> libdir . '/filestorage/file_system.php' ) ; if ( ! empty ( $ CFG -> alternative_file_system_class ) ) { $ class = $ CFG -> alternative_file_system_class ; } else { // The default file_system is the filedir. require_once ( $ CFG -> libdir . '/filestorage/file_system_filedir.php' ) ; $ class = file_system_filedir :: class ; } $ this -> filesystem = new $ class ( ) ; } return $ this -> filesystem ; }
docstring: Complete setup procedure for the file_system component.
  
  @return file_system
docstring_tokens: Complete setup procedure for the file_system component .