Would anyone be opposed to adding the following simple macro, which would be the same as the one we have for Py_RETURN_NONE. I recently found myself doing the Py_INCREF/return dance several times and ended up leaving an incref out in a few spots, which the macro form nicely handles.

diff --git a/Include/object.h b/Include/object.h
--- a/Include/object.h
+++ b/Include/object.h
@@ -792,6 +792,10 @@
 PyAPI_DATA(PyObject) _Py_NotImplementedStruct; /* Don't use this directly */
 #define Py_NotImplemented (&_Py_NotImplementedStruct)

+/* Macro for returning Py_NotImplemented from a function */
+#define Py_RETURN_NOTIMPLEMENTED \
+    return Py_INCREF(Py_NotImplemented), Py_NotImplemented
+
 /* Rich comparison opcodes */
 #define Py_LT 0
 #define Py_LE 1


If this is fine, I can also take care of making the replacements, of which there are apparently 55.

+1

New changeset 77a65b078852 by Brian Curtin in branch 'default':
Add Py_RETURN_NOTIMPLEMENTED macro. Fixes #12724.
http://hg.python.org/cpython/rev/77a65b078852

New changeset d0b0fcbb40db by Brian Curtin in branch 'default':
Replace Py_NotImplemented returns with the macro form Py_RETURN_NOTIMPLEMENTED.
http://hg.python.org/cpython/rev/d0b0fcbb40db

New changeset 3a6782f2a4a8 by Brian Curtin in branch 'default':
News item for #12724
http://hg.python.org/cpython/rev/3a6782f2a4a8

New changeset e88362fb4950 by Brian Curtin in branch 'default':
Add doc for Py_RETURN_NOTIMPLEMENTED, added in #12724.
http://hg.python.org/cpython/rev/e88362fb4950