Issue 17447: Clarify that str.isidentifier doesn't check for reserved keywords.
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
index 7e5f04f..60df11d 100644
--- a/Doc/library/stdtypes.rst
+++ b/Doc/library/stdtypes.rst
@@ -1627,6 +1627,8 @@
Return true if the string is a valid identifier according to the language
definition, section :ref:`identifiers`.
+ Use :func:`keyword.iskeyword` to test for reserved identifiers such as
+ :keyword:`def` and :keyword:`class`.
.. method:: str.islower()