[3.8] bpo-38600: NULL -> ``NULL``. (GH-17001) (GH-17003)
Also fix some other formatting.
(cherry picked from commit e835b31d2b212c3c7820364398979cae2a9740b2)
diff --git a/Doc/c-api/gen.rst b/Doc/c-api/gen.rst
index e4b8d25..7441092 100644
--- a/Doc/c-api/gen.rst
+++ b/Doc/c-api/gen.rst
@@ -27,7 +27,7 @@
.. c:function:: int PyGen_CheckExact(PyObject *ob)
- Return true if *ob*'s type is *PyGen_Type*; *ob* must not be ``NULL``.
+ Return true if *ob*'s type is :c:type:`PyGen_Type`; *ob* must not be ``NULL``.
.. c:function:: PyObject* PyGen_New(PyFrameObject *frame)