Library Management System

pythonCopy codeclass Book:
def __init__(self, title, author, isbn):
    self.title = title
    self.author = author
    self.isbn = isbn
    self.is_borrowed = False
def __str__(self):
    return f"{self.title} by {self.author} (ISBN: {self.isbn}) - {'Borrowed' if self.is_borrowed else 'Available'}"

class Library:
def __init__(self):
    self.books = []
def add_book(self, title, author, isbn):
    book = Book(title, author, isbn)
    self.books.append(book)
    print(f"Added book: {book}")
def view_books(self):
    if not self.books:
        print("No books available in the library.")
        return
    print("\nAvailable Books:")
    for book in self.books:
        print(book)
def borrow_book(self, isbn):
    for book in self.books:
        if book.isbn == isbn:
            if book.is_borrowed:
                print("Sorry, this book is already borrowed.")
            else:
                book.is_borrowed = True
                print(f"You have borrowed: {book}")
            return
    print("Book not found.")
def return_book(self, isbn):
    for book in self.books:
        if book.isbn == isbn:
            if not book.is_borrowed:
                print("This book wasn't borrowed.")
            else:
                book.is_borrowed = False
                print(f"You have returned: {book}")
            return
    print("Book not found.")

def main():
library = Library()

while True:
    print("\nLibrary Management System")
    print("1. Add Book")
    print("2. View Books")
    print("3. Borrow Book")
    print("4. Return Book")
    print("5. Exit")
    choice = input("Choose an option (1-5): ")
    if choice == '1':
        title = input("Enter the book title: ")
        author = input("Enter the author's name: ")
        isbn = input("Enter the ISBN number: ")
        library.add_book(title, author, isbn)
    elif choice == '2':
        library.view_books()
    elif choice == '3':
        isbn = input("Enter the ISBN of the book to borrow: ")
        library.borrow_book(isbn)
    elif choice == '4':
        isbn = input("Enter the ISBN of the book to return: ")
        library.return_book(isbn)
    elif choice == '5':
        print("Exiting the Library Management System.")
        break
    else:
        print("Invalid choice. Please try again.")
if __name__ == "__main__":
main()

Step 2: Running the Library Management System

1. Open your terminal (or command prompt).
2. Navigate to the directory where you saved library_management.py.
3. Run the script using the command:bashCopy codepython library_management.py

How It Works

• Book Class: Represents a book with attributes for title, author, ISBN, and whether it is borrowed.
• Library Class: Manages a list of books, including adding books, viewing available books, borrowing, and returning books.
• User Interaction: The command-line interface allows users to choose actions like adding a book, viewing the library, borrowing a book, or returning a book.

Example Usage

1. Add Book: Choose option 1 and enter the book title, author, and ISBN to add a new book.
2. View Books: Choose option 2 to see all available books in the library.
3. Borrow Book: Choose option 3 and enter the ISBN of the book you want to borrow.
4. Return Book: Choose option 4 and enter the ISBN of the book you want to return.
5. Exit: Choose option 5 to exit the system.