Issue #12669: Fix test_curses so that it can run on the buildbots.
diff --git a/Lib/test/test_curses.py b/Lib/test/test_curses.py
index b9ff346..c767e93 100644
--- a/Lib/test/test_curses.py
+++ b/Lib/test/test_curses.py
@@ -276,11 +276,11 @@
         curses.resetty()
 
 def test_main():
-    if not sys.stdout.isatty():
-        raise unittest.SkipTest("sys.stdout is not a tty")
+    if not sys.__stdout__.isatty():
+        raise unittest.SkipTest("sys.__stdout__ is not a tty")
     # testing setupterm() inside initscr/endwin
     # causes terminal breakage
-    curses.setupterm(fd=sys.stdout.fileno())
+    curses.setupterm(fd=sys.__stdout__.fileno())
     try:
         stdscr = curses.initscr()
         main(stdscr)