/usr/lib/python2.7/dist-packages/sphinx/ext/ is in python-sphinx 1.2.2+dfsg-1ubuntu1.
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/usr/lib/python2.7/dist-packages/sphinx/ext/__init__.py
/usr/lib/python2.7/dist-packages/sphinx/ext/autodoc.py
/usr/lib/python2.7/dist-packages/sphinx/ext/autosummary/
/usr/lib/python2.7/dist-packages/sphinx/ext/autosummary/__init__.py
/usr/lib/python2.7/dist-packages/sphinx/ext/autosummary/generate.py
/usr/lib/python2.7/dist-packages/sphinx/ext/coverage.py
/usr/lib/python2.7/dist-packages/sphinx/ext/doctest.py
/usr/lib/python2.7/dist-packages/sphinx/ext/extlinks.py
/usr/lib/python2.7/dist-packages/sphinx/ext/graphviz.py
/usr/lib/python2.7/dist-packages/sphinx/ext/ifconfig.py
/usr/lib/python2.7/dist-packages/sphinx/ext/inheritance_diagram.py
/usr/lib/python2.7/dist-packages/sphinx/ext/intersphinx.py
/usr/lib/python2.7/dist-packages/sphinx/ext/jsmath.py
/usr/lib/python2.7/dist-packages/sphinx/ext/linkcode.py
/usr/lib/python2.7/dist-packages/sphinx/ext/mathbase.py
/usr/lib/python2.7/dist-packages/sphinx/ext/mathjax.py
/usr/lib/python2.7/dist-packages/sphinx/ext/oldcmarkup.py
/usr/lib/python2.7/dist-packages/sphinx/ext/pngmath.py
/usr/lib/python2.7/dist-packages/sphinx/ext/todo.py
/usr/lib/python2.7/dist-packages/sphinx/ext/viewcode.py