bpo-17305: Link to the third-party idna package. (GH-25208)
So long as we don't have idna2008 in the standard library, we should at least point people to the third-party solution.
diff --git a/Doc/library/codecs.rst b/Doc/library/codecs.rst
index 3169ae5..b15d293 100644
--- a/Doc/library/codecs.rst
+++ b/Doc/library/codecs.rst
@@ -1417,6 +1417,9 @@
Internationalized Domain Names (IDN)). It builds upon the ``punycode`` encoding
and :mod:`stringprep`.
+If you need the IDNA 2008 standard from :rfc:`5891` and :rfc:`5895`, use the
+third-party `idna module <https://pypi.org/project/idna/>_`.
+
These RFCs together define a protocol to support non-ASCII characters in domain
names. A domain name containing non-ASCII characters (such as
``www.Alliancefrançaise.nu``) is converted into an ASCII-compatible encoding