bpo-38600: NULL -> ``NULL``. (GH-17001)
Also fix some other formatting.
diff --git a/Doc/c-api/object.rst b/Doc/c-api/object.rst
index 0b93064..9d11551 100644
--- a/Doc/c-api/object.rst
+++ b/Doc/c-api/object.rst
@@ -399,7 +399,7 @@
To get actual number of arguments, use
:c:func:`PyVectorcall_NARGS(nargsf) <PyVectorcall_NARGS>`.
- *kwnames* can be either NULL (no keyword arguments) or a tuple of keyword
+ *kwnames* can be either ``NULL`` (no keyword arguments) or a tuple of keyword
names, which must be strings. In the latter case, the values of the keyword
arguments are stored in *args* after the positional arguments.
The number of keyword arguments does not influence *nargsf*.