bpo-40268: Remove unused structmember.h includes (GH-19530)
If only offsetof() is needed: include stddef.h instead.
When structmember.h is used, add a comment explaining that
PyMemberDef is used.
diff --git a/Modules/_io/winconsoleio.c b/Modules/_io/winconsoleio.c
index 94760ac..a83ef37 100644
--- a/Modules/_io/winconsoleio.c
+++ b/Modules/_io/winconsoleio.c
@@ -12,7 +12,7 @@
#ifdef MS_WINDOWS
-#include "structmember.h"
+#include "structmember.h" // PyMemberDef
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif