From 6426c3077c8048bb3fa5bfcec6be80f73476b534 Mon Sep 17 00:00:00 2001
From: Mariusz Felisiak <felisiak.mariusz@gmail.com>
Date: Thu, 16 Sep 2021 07:12:58 +0200
Subject: [PATCH] Fixed #33107 -- Fixed import_string() crash on not fully
 initialized modules.

Regression in ecf87ad513fd8af6e4a6093ed918723a7d88d5ca.

Thanks Collin Anderson for the report.
---
 django/utils/module_loading.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/django/utils/module_loading.py b/django/utils/module_loading.py
index 1df82b1c32..d42b9a5f22 100644
--- a/django/utils/module_loading.py
+++ b/django/utils/module_loading.py
@@ -7,7 +7,11 @@ from importlib.util import find_spec as importlib_find
 
 def cached_import(module_path, class_name):
     modules = sys.modules
-    if module_path not in modules:
+    if module_path not in modules or (
+        # Module is not fully initialized.
+        getattr(modules[module_path], '__spec__', None) is not None and
+        getattr(modules[module_path].__spec__, '_initializing', False) is True
+    ):
         import_module(module_path)
     return getattr(modules[module_path], class_name)