diff --git a/lms/djangoapps/shoppingcart/models.py b/lms/djangoapps/shoppingcart/models.py
index 895f466273..a738dd2107 100644
--- a/lms/djangoapps/shoppingcart/models.py
+++ b/lms/djangoapps/shoppingcart/models.py
@@ -6,7 +6,7 @@ from django.core.exceptions import ObjectDoesNotExist
 from django.contrib.auth.models import User
 from django.utils.translation import ugettext as _
 from model_utils.managers import InheritanceManager
-from courseware.courses import course_image_url, get_course_about_section
+from courseware.courses import get_course_about_section
 
 from xmodule.modulestore.django import modulestore
 from xmodule.course_module import CourseDescriptor
@@ -66,6 +66,7 @@ class Order(models.Model):
 
     @property
     def total_cost(self):
+        """ Return the total cost of the order """
         return sum(i.line_cost for i in self.orderitem_set.filter(status=self.status))
 
     def clear(self):
@@ -79,6 +80,19 @@ class Order(models.Model):
         """
         Call to mark this order as purchased.  Iterates through its OrderItems and calls
         their purchased_callback
+
+        `first` - first name of person billed (e.g. John)
+        `last` - last name of person billed (e.g. Smith)
+        `street1` - first line of a street address of the billing address (e.g. 11 Cambridge Center)
+        `street2` - second line of a street address of the billing address (e.g. Suite 101)
+        `city` - city of the billing address (e.g. Cambridge)
+        `state` - code of the state, province, or territory of the billing address (e.g. MA)
+        `postalcode` - postal code of the billing address (e.g. 02142)
+        `country` - country code of the billing address (e.g. US)
+        `ccnum` - last 4 digits of the credit card number of the credit card billed (e.g. 1111)
+        `cardtype` - 3-digit code representing the card type used (e.g. 001)
+        `processor_reply_dump` - all the parameters returned by the processor
+
         """
         self.status = 'purchased'
         self.purchase_time = datetime.now(pytz.utc)
diff --git a/lms/djangoapps/shoppingcart/views.py b/lms/djangoapps/shoppingcart/views.py
index ce94ca8428..8e56971d47 100644
--- a/lms/djangoapps/shoppingcart/views.py
+++ b/lms/djangoapps/shoppingcart/views.py
@@ -1,13 +1,14 @@
 import logging
 from django.http import HttpResponse, HttpResponseRedirect, HttpResponseNotFound, HttpResponseForbidden, Http404
 from django.utils.translation import ugettext as _
+from django.views.decorators.http import require_POST
 from django.core.urlresolvers import reverse
 from django.views.decorators.csrf import csrf_exempt
 from django.contrib.auth.decorators import login_required
 from student.models import CourseEnrollment
 from xmodule.modulestore.exceptions import ItemNotFoundError
 from mitxmako.shortcuts import render_to_response
-from .models import *
+from .models import Order, PaidCourseRegistration, CertificateItem, OrderItem
 from .processors import process_postpay_callback, render_purchase_form_html
 
 log = logging.getLogger("shoppingcart")
@@ -38,6 +39,9 @@ def add_course_to_cart(request, course_id):
 
 @login_required
 def register_for_verified_cert(request, course_id):
+    """
+    Add a CertificateItem to the cart
+    """
     cart = Order.get_cart_for_user(request.user)
     CertificateItem.add_to_order(cart, course_id, 30, 'verified')
     return HttpResponse("Added")
@@ -77,6 +81,7 @@ def remove_item(request):
 
 
 @csrf_exempt
+@require_POST
 def postpay_callback(request):
     """
     Receives the POST-back from processor.
@@ -111,7 +116,7 @@ def show_receipt(request, ordernum):
         raise Http404('Order not found!')
 
     order_items = order.orderitem_set.all()
-    any_refunds = "refunded" in [i.status for i in order_items]
+    any_refunds = any(i.status == "refunded" for i in order_items)
     return render_to_response('shoppingcart/receipt.html', {'order': order,
                                                             'order_items': order_items,
                                                             'any_refunds': any_refunds})