* Throw 404 instead of a 503 in Event Mixins if the related event does

not exist.
* Changes in the KyuDanRanking View to be more stable if we get bogus
kwargs.

src/mahjong_ranking/forms.py

@@ -10,6 +10,7 @@ from django import forms
 from django.utils.translation import ugettext as _
 
 from . import models
+from events.models import Event
 
 USER_MODEL = get_user_model()
 
@@ -58,3 +59,8 @@ class HanchanAdminForm(HanchanForm):
         """ Extend the formfields to add the confirmed checkbox. """
         model = models.Hanchan
         fields = HanchanForm.Meta.fields + ('confirmed',)
+
+HanchanFormset = forms.inlineformset_factory(Event, models.Hanchan,
+                                             form=HanchanForm,
+                                             extra=1,
+                                             can_delete=True)