undefine SET_SYS_FROM_STRING_BORROW after its done being used (closes #21089)

diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index 9ec3bfa07b5050ec0fe174395b193475b033dffb..64de2bf258e8489a771e5d5f82b8833cd43501c7 100644 (file)
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -1799,6 +1799,7 @@ _PySys_Init(void)
 #endif
 
 #undef SET_SYS_FROM_STRING
+#undef SET_SYS_FROM_STRING_BORROW
     if (PyErr_Occurred())
         return NULL;
     return m;