Fixed #17379 -- Removed management commands deactivation of the locale.

django/apps/registry.py

@@ -124,6 +124,11 @@ class Apps:
     def check_apps_ready(self):
         """Raise an exception if all apps haven't been imported yet."""
         if not self.apps_ready:
+            from django.conf import settings
+            # If "not ready" is due to unconfigured settings, accessing
+            # INSTALLED_APPS raises a more helpful ImproperlyConfigured
+            # exception.
+            settings.INSTALLED_APPS
             raise AppRegistryNotReady("Apps aren't loaded yet.")
 
     def check_models_ready(self):