Patch #1490224: set time.altzone correctly on Cygwin.
diff --git a/Modules/timemodule.c b/Modules/timemodule.c
index f089ecd..742d6bf 100644
--- a/Modules/timemodule.c
+++ b/Modules/timemodule.c
@@ -713,7 +713,7 @@
 #ifdef __CYGWIN__
 	tzset();
 	PyModule_AddIntConstant(m, "timezone", _timezone);
-	PyModule_AddIntConstant(m, "altzone", _timezone);
+	PyModule_AddIntConstant(m, "altzone", _timezone-3600);
 	PyModule_AddIntConstant(m, "daylight", _daylight);
 	PyModule_AddObject(m, "tzname",
 			   Py_BuildValue("(zz)", _tzname[0], _tzname[1]));