How to modify existing model instance in django?

In Django, I am trying to modify the title of the existing book with id. My views.py file consists of

b=Books.objects.filter(book_id__iexact=book)
b.title = "Narnia"
b.save()

I am getting error and unable to save the model instance.

>Solution :

Try using get method instead of filter. When you use filter you are using a queryset object. Instead of using Books.objects.filter(book_id__iexact=book) try using b=Books.objects.get(book_id__iexact=book)