diff -r 5c7fdd4521be Doc/library/re.rst
--- a/Doc/library/re.rst	Tue Feb 07 08:37:23 2017 +0100
+++ b/Doc/library/re.rst	Tue Feb 07 16:04:49 2017 +0100
@@ -42,6 +42,13 @@
 that don't require you to compile a regex object first, but miss some
 fine-tuning parameters.
 
+.. seealso::
+
+   The `regex module on PyPI <https://pypi.python.org/pypi/regex/>`_.
+   That is a third-party alternative regular expression module, mostly
+   compatible with the :mod:`re` module's API, but with additional
+   features.
+
 
 .. _re-syntax: