def get(self):
username = self.get_secure_cookie("user")
session_id = self.get_secure_cookie("sessionID")
query_id = username or session_id
books = Cart.get(query_id)
self.render('cart.html', books=books, page_title="My Cart")
def post(self, isbn=None):
username = self.get_secure_cookie("user")
session_id = self.get_secure_cookie("sessionID")
query_id = username or session_id
Cart.remove(query_id)
self.redirect("/cart")
