From 701acd1ec5f304cbb69707bd755ccc9dc87c08cf Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Sat, 7 Mar 2015 08:15:41 +0530
Subject: [PATCH] ...

---
 src/calibre/gui2/__init__.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/calibre/gui2/__init__.py b/src/calibre/gui2/__init__.py
index 0e291f4380..fd68a08246 100644
--- a/src/calibre/gui2/__init__.py
+++ b/src/calibre/gui2/__init__.py
@@ -1180,7 +1180,7 @@ def must_use_qt():
     RuntimeError if using Qt is not possible, which will happen if the current
     thread is not the main GUI thread. On linux, it uses a special QPA headless
     plugin, so that the X server does not need to be running. '''
-    global gui_thread, _store_app
+    global gui_thread
     ensure_app()
     if gui_thread is None:
         gui_thread = QThread.currentThread()