gh-141004: Document C APIs for dictionary keys, values, and items

Doc/c-api/dict.rst

@@ -426,3 +426,55 @@ Dictionary Objects
    it before returning.
 
    .. versionadded:: 3.12
+
+
+.. c:function:: int PyDictViewSet_Check(PyObject *op)
+
+   Return true if *op* is a view of a set inside a dictionary. This is currently
+   equivalent to :c:expr:`PyDictKeys_Check(op) || PyDictItems_Check(op)`. This
+   function always succeeds.
+
+
+Dictionary Keys Objects
+^^^^^^^^^^^^^^^^^^^^^^^
+
+.. c:var:: PyTypeObject PyDictKeys_Type
+
+   Type object for a view of dictionary keys. In Python, this is the type of
+   the object returned by :meth:`dict.keys`.
+
+
+.. c:function:: int PyDictKeys_Check(PyObject *op)
+
+   Return true if *op* is an instance of a dictionary keys view. This function
+   always succeeds.
+
+
+Dictionary Values Objects
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. c:var:: PyTypeObject PyDictValues_Type
+
+   Type object for a view of dictionary values. In Python, this is the type of
+   the object returned by :meth:`dict.values`.
+
+
+.. c:function:: int PyDictValues_Check(PyObject *op)
+
+   Return true if *op* is an instance of a dictionary values view. This function
+   always succeeds.
+
+
+Dictionary Items Objects
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. c:var:: PyTypeObject PyDictItems_Type
+
+   Type object for a view of dictionary items. In Python, this is the type of
+   the object returned by :meth:`dict.items`.
+
+
+.. c:function:: int PyDictItems_Check(PyObject *op)
+
+   Return true if *op* is an instance of a dictionary items view. This function
+   always succeeds.