bpo-40170: Always define PyIter_Check() as a function (GH-24548)
diff --git a/Doc/c-api/iter.rst b/Doc/c-api/iter.rst
index 74fb557..5706777 100644
--- a/Doc/c-api/iter.rst
+++ b/Doc/c-api/iter.rst
@@ -9,8 +9,8 @@
.. c:function:: int PyIter_Check(PyObject *o)
- Return true if the object *o* supports the iterator protocol. This
- function always succeeds.
+ Return non-zero if the object *o* supports the iterator protocol, and ``0``
+ otherwise. This function always succeeds.
.. c:function:: PyObject* PyIter_Next(PyObject *o)