Design a file access system to allow certain users read and write access to a file, depending on authorization set up by the system. The instructions should be of the format:

READ (F, User A): attempt by User A to read file F READ (F, User A): attempt by User A to store a possibly modified copy of F Each file has a header record, which contains authorization privileges; that is, a list of users who can read and write.The file is to be encrypted by a key that is not shared by the users but known only to the system.