Add versionchanged.

Author: serhiy-storchaka

Doc/c-api/unicode.rst

@@ -1842,8 +1842,6 @@ object.
    On success, return ``0``.
    On error, set an exception, leave the writer unchanged, and return ``-1``.
 
-   .. versionadded:: 3.14
-
 .. c:function:: int PyUnicodeWriter_WriteWideChar(PyUnicodeWriter *writer, const wchar_t *str, Py_ssize_t size)
 
    Write the wide string *str* into *writer*.
@@ -1879,6 +1877,10 @@ object.
    On success, return ``0``.
    On error, set an exception, leave the writer unchanged, and return ``-1``.
 
+   .. versionchanged:: 3.14.4
+
+      Added support for ``NULL``.
+
 .. c:function:: int PyUnicodeWriter_WriteSubstring(PyUnicodeWriter *writer, PyObject *str, Py_ssize_t start, Py_ssize_t end)
 
    Write the substring ``str[start:end]`` into *writer*.