the unique id for that message in the form ``'response mesgnum uid``, otherwise
result is list ``(response, ['mesgnum uid', ...], octets)``.
- Try to switch to UTF-8 mode. Returns the server response if sucessful,
+
+.. method:: POP3.utf8()
+
++ Try to switch to UTF-8 mode. Returns the server response if successful,
+ raises :class:`error_proto` if not. Specified in :RFC:`6856`.
+
+ .. versionadded:: 3.5
+
+
.. method:: POP3.stls(context=None)
Start a TLS session on the active connection as specified in :rfc:`2595`.