Add missing docstrings

cas_server/models.py

@@ -737,6 +737,7 @@ class Ticket(models.Model):
     TIMEOUT = settings.CAS_TICKET_TIMEOUT
 
     class DoesNotExist(Exception):
+        """raised in :meth:`Ticket.get` then ticket prefix and ticket classes mismatch"""
         pass
 
     def __str__(self):

cas_server/tests/test_view.py

@@ -1193,6 +1193,7 @@ class ValidateServiceTestCase(TestCase, XmlContent):
         self.assert_success(response, settings.CAS_TEST_USER, settings.CAS_TEST_ATTRIBUTES)
 
     def test_validate_proxy(self):
+        """test ProxyTicket validation on /proxyValidate and /serviceValidate"""
         ticket = get_proxy_ticket(self.service)
         client = Client()
         # requesting validation with a good (ticket, service)