bpo-42528: Improve the docs of most Py*_Check{,Exact} API calls (GH-23602)
I think that none of these API calls can fail, but only few of them are
documented as such. Add the sentence "This function always succeeds" (which is
the same already used e.g. by PyNumber_Check) to all of them.diff --git a/Doc/c-api/function.rst b/Doc/c-api/function.rst
index bb416f4..2096882 100644
--- a/Doc/c-api/function.rst
+++ b/Doc/c-api/function.rst
@@ -26,7 +26,7 @@
.. c:function:: int PyFunction_Check(PyObject *o)
Return true if *o* is a function object (has type :c:data:`PyFunction_Type`).
- The parameter must not be ``NULL``.
+ The parameter must not be ``NULL``. This function always succeeds.
.. c:function:: PyObject* PyFunction_New(PyObject *code, PyObject *globals)