用python写一个图书馆馆借阅系统

好的，下面是一个简单的图书馆借阅系统的Python代码：

class Book:
    def __init__(self, title, author, genre, isbn):
        self.title = title
        self.author = author
        self.genre = genre
        self.isbn = isbn
        self.is_borrowed = False

    def __str__(self):
        return f"{self.title} by {self.author} ({self.genre}), ISBN: {self.isbn}"

class Library:
    def __init__(self, name):
        self.name = name
        self.books = []

    def add_book(self, book):
        self.books.append(book)

    def remove_book(self, book):
        self.books.remove(book)

    def borrow_book(self, book):
        if not book.is_borrowed:
            book.is_borrowed = True
            print(f"You have borrowed {book}.")
        else:
            print(f"{book} is already borrowed.")

    def return_book(self, book):
        if book in self.books:
            if book.is_borrowed:
                book.is_borrowed = False
                print(f"You have returned {book}.")
            else:
                print(f"{book} is not borrowed.")
        else:
            print(f"{book} is not part of the library.")

    def available_books(self):
        available = [book for book in self.books if not book.is_borrowed]
        if len(available) == 0:
            print("No books available.")
        else:
            print("Available books:")
            for book in available:
                print(book)

def main():
    library = Library("My Library")

    book1 = Book("The Catcher in the Rye", "J.D. Salinger", "Fiction", "0316769177")
    book2 = Book("To Kill a Mockingbird", "Harper Lee", "Fiction", "0446310786")
    book3 = Book("1984", "George Orwell", "Fiction", "0451524934")

    library.add_book(book1)
    library.add_book(book2)
    library.add_book(book3)

    library.available_books()

    library.borrow_book(book1)
    library.borrow_book(book1)
    library.borrow_book(book2)

    library.return_book(book1)
    library.return_book(book3)

    library.available_books()

if __name__ == "__main__":
    main()

这个简单的图书馆馆借阅系统包含两个类：`Book` 和 `Library`。`Book` 类表示一本书，包括书名、作者、类型和 ISBN 等信息，以及一个标志表示书是否被借出。`Library` 类表示一个图书馆，包含图书馆的名字和所有的书籍。它还有一些方法，可以添加、删除、借出和归还书籍，以及列出可用的书籍。

在 `main()` 函数中，我们创建了一个名为 `My Library` 的新图书馆，添加了三本书，并尝试借出和归还一些书籍。最后，我们列出了可用的书籍。