Issue #20978: pyflakes: fix undefined names
diff --git a/Lib/tempfile.py b/Lib/tempfile.py
index 05d4cab..57e8a82 100644
--- a/Lib/tempfile.py
+++ b/Lib/tempfile.py
@@ -72,7 +72,7 @@
     # file doesn't exist.
     def _stat(fn):
         fd = _os.open(fn, _os.O_RDONLY)
-        os.close(fd)
+        _os.close(fd)
 
 def _exists(fn):
     try: