update CodeTools link; thanks to Robert Kern from docs@
diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst
index 88d7981..4c5b649 100644
--- a/Doc/library/collections.rst
+++ b/Doc/library/collections.rst
@@ -98,7 +98,7 @@
.. seealso::
* The `MultiContext class
- <http://svn.enthought.com/svn/enthought/CodeTools/trunk/enthought/contexts/multi_context.py>`_
+ <https://github.com/enthought/codetools/blob/4.0.0/codetools/contexts/multi_context.py>`_
in the Enthought `CodeTools package
<https://github.com/enthought/codetools>`_ has options to support
writing to any mapping in the chain.