Fix the issue: AppRegistryNotReady exception while syncdb with Django 1.7, according to

this suggestion in django document:
https://docs.djangoproject.com/en/1.7/ref/applications/#troubleshooting

Author: Han He

xadmin/models.py

@@ -15,7 +15,7 @@
 import datetime
 import decimal
 
-if django.VERSION[1] > 4:
+if 4 < django.VERSION[1] < 7:
     AUTH_USER_MODEL = django.contrib.auth.get_user_model()
 else:
     AUTH_USER_MODEL = getattr(settings, 'AUTH_USER_MODEL', 'auth.User')