Fixed reference to Question model in management command how-to.

docs/howto/custom-management-commands.txt

@@ -49,7 +49,7 @@ To implement the command, edit ``polls/management/commands/closepoll.py`` to
 look like this::
 
     from django.core.management.base import BaseCommand, CommandError
-    from polls.models import Poll
+    from polls.models import Question as Poll
 
     class Command(BaseCommand):
         help = 'Closes the specified poll for voting'
@@ -88,8 +88,8 @@ The new custom command can be called using ``python manage.py closepoll
 The ``handle()`` method takes one or more ``poll_ids`` and sets ``poll.opened``
 to ``False`` for each one. If the user referenced any nonexistent polls, a
 :exc:`CommandError` is raised. The ``poll.opened`` attribute does not exist in
-the :doc:`tutorial</intro/tutorial01>` and was added to ``polls.models.Poll``
-for this example.
+the :doc:`tutorial</intro/tutorial01>` and was added to
+``polls.models.Question`` for this example.
 
 .. _custom-commands-options: