bpo-36763: Implement PyWideStringList_Insert() of PEP 587 (GH-15423)
diff --git a/Doc/c-api/init_config.rst b/Doc/c-api/init_config.rst
index d2c1f9a..5fd836d 100644
--- a/Doc/c-api/init_config.rst
+++ b/Doc/c-api/init_config.rst
@@ -72,8 +72,12 @@
.. c:function:: PyStatus PyWideStringList_Insert(PyWideStringList *list, Py_ssize_t index, const wchar_t *item)
- Insert *item* into *list* at *index*. If *index* is greater than *list*
- length, just append *item* to *list*.
+ Insert *item* into *list* at *index*.
+
+ If *index* is greater than or equal to *list* length, append *item* to
+ *list*.
+
+ *index* must be greater than or equal to 0.
Python must be preinitialized to call this function.