diff --git a/unwind/models.py b/unwind/models.py
index 56ad2c5..7fdbb8c 100644
--- a/unwind/models.py
+++ b/unwind/models.py
@@ -195,7 +195,7 @@ class Movie:
             return
 
         for field in fields(Movie):
-            if getattr(self, field.name) is None and field.default_factory:
+            if getattr(self, field.name) is None and callable(field.default_factory):
                 setattr(self, field.name, field.default_factory())
 
         self._is_lazy = False