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/gen.rst b/Doc/c-api/gen.rst
index 7441092..0eb5922 100644
--- a/Doc/c-api/gen.rst
+++ b/Doc/c-api/gen.rst
@@ -22,12 +22,14 @@
.. c:function:: int PyGen_Check(PyObject *ob)
- Return true if *ob* is a generator object; *ob* must not be ``NULL``.
+ Return true if *ob* is a generator object; *ob* must not be ``NULL``. This
+ function always succeeds.
.. c:function:: int PyGen_CheckExact(PyObject *ob)
- Return true if *ob*'s type is :c:type:`PyGen_Type`; *ob* must not be ``NULL``.
+ Return true if *ob*'s type is :c:type:`PyGen_Type`; *ob* must not be
+ ``NULL``. This function always succeeds.
.. c:function:: PyObject* PyGen_New(PyFrameObject *frame)