Prepare an abstraction for a library and book lending system. A customer can borrow more than one book from the library. Functionalities to be implemented include:

Adding and removing books from the list of borrowed books. Return - if it occurs on time, there is no penalty; if not, each day of delay incurs penalty points - when the penalty points reach 10, borrowing books is not allowed for a month, after which the points reset. Adding books to the list. Removing books from the list. Borrowing book(s) for a specific user. Returning the borrowed book(s).