Removed get_user_model from module level

persistent_messages/models.py

@@ -1,6 +1,7 @@
 import persistent_messages
 from persistent_messages.constants import PERSISTENT_MESSAGE_LEVELS
 from django.db import models
+from django.conf import settings
 from django.contrib.auth import get_user_model
 from django.utils.encoding import force_unicode
 from django.contrib import messages
@@ -11,7 +12,7 @@
 LEVEL_TAGS = utils.get_level_tags()
 
 class Message(models.Model):
-    user = models.ForeignKey(get_user_model(), blank=True, null=True)
+    user = models.ForeignKey(settings.AUTH_USER_MODEL, blank=True, null=True)
     from_user = models.ForeignKey(get_user_model(), blank=True, null=True, related_name="from_user")
     subject = models.CharField(max_length=255, blank=True, default='')
     message = models.TextField()
@@ -83,4 +84,4 @@ def _get_tags(self):
             return u' '.join([label_tag, read_tag])
         return read_tag
     tags = property(_get_tags)
-
+