diff --git a/django/db/__init__.py b/django/db/__init__.py
index 69a6d2b18d..60fe8f6ce2 100644
--- a/django/db/__init__.py
+++ b/django/db/__init__.py
@@ -1,3 +1,5 @@
+import warnings
+
 from django.conf import settings
 from django.core import signals
 from django.core.exceptions import ImproperlyConfigured