Use https://docs.moodle.org/dev/Automatic_class_loading
Call the class something like local_azurefilestorage_file_system, and define it in local/azurefilestorage/classes/file_system.php.
Use https://docs.moodle.org/dev/Automatic_class_loading
Call the class something like local_azurefilestorage_file_system, and define it in local/azurefilestorage/classes/file_system.php.
Thanks, this method solved my problem