How to remove 1 record from a db.Table using Flask_SQLAlchemy?

user_instance.books.remove(book_instance)
db.session.commit()

def remove(book_id):
    # get the user
    user = db.session.query(User).filter_by(email=session['email']).first()

    # Find the book by its id
    book_rm = Book.query.get(book_id)

    user.books.remove(book_rm)
    db.session.commit()