library_management.py

books = []

def login():
    username = "likitha"
    password = "1234"
    user = input("Enter your name: ")
    pwd = input("Enter password: ")
    
    if user == username and pwd == password:
        print("Login successful")  # fixed spelling
        return True
    else:
        print("Enter valid details")
        return False

def add_book():
    book_id = input("Enter Book id: ").strip()
    author = input("Enter book Author: ").strip()
    title = input("Enter book Title: ").strip()
    quantity = int(input("Enter book Quantity: "))

    book = {"Book ID": book_id, "Title": title, "Author": author, "Quantity": quantity}
    books.append(book)
    print("Book added successfully")

def search_book():
    book_id = input("Enter Book ID to search").strip()
    found = False
    for book in books:
        if book["Book ID"] == book_id:
            print("\nBook Found!")
            print("Book ID:", book["Book ID"])
            print("Title:", book["Title"])
            print("Author:", book["Author"])
            print("Quantity:", book["Quantity"])
            found = True
            break
    if not found:
        print("Book not found!")

def issue_book():
    book_id = input("Enter Book ID to issue").strip()
    found = False
    for book in books:
        if book["Book ID"] == book_id:
            found = True
            if book["Quantity"] > 0:
                book["Quantity"] -= 1
                print("\nBook issued successfully!")
            else:
                print("\nSorry! This book is out of stock.")
            break
    if not found:
        print("\nBook not found!")

def return_book():
    book_id = input("Enter book id").strip()
    found = False
    for book in books:
        if book["Book ID"] == book_id:  # fixed typo
            book["Quantity"] += 1
            print("Book returned successfully")
            found = True
            break
    if not found:
        print("\nBook not found!")

def calculate_fine():
    days = int(input("Enter no of days book was kept"))
    allowed_days = 7
    fine_per_day = 5
    if days <= allowed_days:
        print("No fine")
    else:
        fine = (days - allowed_days) * fine_per_day
        print("Fine Amount =", fine)

if login():
    while True:
        print("\n========== LIBRARY MANAGEMENT SYSTEM ==========")
        print("1. Add Book")
        print("2. Search Book")
        print("3. Issue Book")
        print("4. Return Book")
        print("5. Fine Calculation")
        print("6. Exit")

        choice = input("Enter Your Choice: ")

        if choice == "1":
            add_book()
        elif choice == "2":
            search_book()
        elif choice == "3":
            issue_book()
        elif choice == "4":
            return_book()
        elif choice == "5":
            calculate_fine()
        elif choice == "6":
            break
        else:
            print("Invalid Choice!")