帮我写一个图书管理系统的完整代码

当然可以帮你写一个图书管理系统的代码。以下是一个简单的示例，包含了基本的图书管理功能，包括添加图书、借阅图书、归还图书和查询图书等操作。

class Book:
    def __init__(self, title, author, available=True):
        self.title = title
        self.author = author
        self.available = available

    def __str__(self):
        return f"{self.title} by {self.author}"

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

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

    def borrow_book(self, title):
        for book in self.books:
            if book.title == title and book.available:
                book.available = False
                return f"You have borrowed '{book}'."
        return "Book not available for borrowing."

    def return_book(self, title):
        for book in self.books:
            if book.title == title and not book.available:
                book.available = True
                return f"You have returned '{book}'."
        return "Invalid book or already returned."

    def search_book(self, title):
        for book in self.books:
            if book.title == title:
                return f"'{book}' is available." if book.available else f"'{book}' is currently borrowed."
        return "Book not found in the library."

# 示例用法
library = Library()

book1 = Book("Python Crash Course", "Eric Matthes")
book2 = Book("Clean Code", "Robert C. Martin")
book3 = Book("The Pragmatic Programmer", "Andrew Hunt, David Thomas")

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

print(library.search_book("Clean Code"))  # 输出: 'Clean Code by Robert C. Martin' is available.

print(library.borrow_book("Clean Code"))  # 输出: You have borrowed 'Clean Code by Robert C. Martin'.
print(library.search_book("Clean Code"))  # 输出: 'Clean Code by Robert C. Martin' is currently borrowed.

print(library.return_book("Clean Code"))  # 输出: You have returned 'Clean Code by Robert C. Martin'.
print(library.search_book("Clean Code"))  # 输出: 'Clean Code by Robert C. Martin' is available.

这只是一个简单的示例，你可以根据实际需求进行扩展和修改。希望对你有帮助！