--- Python-2.7.13/Modules/posixmodule.c	2016-12-17 21:05:07.000000000 +0100
+++ Python-2.7.13-patch/Modules/posixmodule.c	2018-05-31 20:13:42.000000000 +0100
@@ -2828,6 +2828,7 @@
 }
 
 
+#undef HAVE_SYSTEM
 #ifdef HAVE_SYSTEM
 PyDoc_STRVAR(posix_system__doc__,
 "system(command) -> exit_status\n\n\