Added failed mix delete management command

spa/management/commands/deletefailed.py

@@ -0,0 +1,10 @@
+from django.core.management.base import NoArgsCommand
+from spa.models import Mix
+
+
+class Command(NoArgsCommand):
+    def handle(self, *args, **options):
+        candidates = Mix.objects.filter(waveform_generated=True)
+        for mix in candidates:
+            print "Deleting: %s" % mix.title
+            #candidates.delete()