Functions in python What is the error in the code?simple library implementation code
members = [] books = [] borrowed = {} ADD_MEMBER = 1 DELETE_MEMBER = 2 ADD_BOOK = 3 DELETE_BOOK = 4 FIND_BORROWER = 5 ISSUE_BOOK = 6 RETURN_BOOK = 7 LIST_MEMBERS = 8 LIST_BOOKS = 9 PRINT_HELP = 10 EXIT = 0 def main(): # print menu print("The commands are:") print(" ", ADD_MEMBER, "to add a member") print(" ", DELETE_MEMBER, "to delete a member") print(" ", ADD_BOOK, "to add a book") print(" ", DELETE_BOOK, "to delete a book") print(" ", FIND_BORROWER, "to find out borrower of a book") print(" ", ISSUE_BOOK, "to issue a book") print(" ", RETURN_BOOK, "to return a book") print(" ", LIST_MEMBERS, "to list members") print(" ", LIST_BOOKS, "to list books") print(" ", PRINT_HELP, "to print this menu") print(" ", EXIT, "to quit") def add_list_entry(members,member,books,book): command=int(input("Enter command:")) if command == ADD_MEMBER: entry=input("Enter member name:") members.append(entry) return entry else: command == ADD_BOOK entry_book=input("Enter book name:") books.append(entry_book) return entry_book def delete_list_entry(members,member,books,book): command=int(input("Enter command:")) if command == DELETE_MEMBER: entry_member=input("Enter member name:") members.remove(entry_member) return entry_member else: command == DELETE_BOOK entry_books=input("Enter book name:") books.remove(entry_books) return entry_books def borrow_book(book_issued): command=int(input("Enter command:")) if command == FIND_BORROWER: book_name = input("Enter book name: ") if book_name not in books: print("No book named", book_name) elif book_name not in borrowed: print(book_name, "is not borrowed") else: print(borrowed[book_name]) return book_name def book_issued(book): command=int(input("Enter command:")) if command == ISSUE_BOOK: book_names