/usr/lib/python3/dist-packages/sphinx/ext/ is in python3-sphinx 1.3.6-2ubuntu1.
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/usr/lib/python3/dist-packages/sphinx/ext/__init__.py
/usr/lib/python3/dist-packages/sphinx/ext/autodoc.py
/usr/lib/python3/dist-packages/sphinx/ext/autosummary/
/usr/lib/python3/dist-packages/sphinx/ext/autosummary/__init__.py
/usr/lib/python3/dist-packages/sphinx/ext/autosummary/generate.py
/usr/lib/python3/dist-packages/sphinx/ext/coverage.py
/usr/lib/python3/dist-packages/sphinx/ext/doctest.py
/usr/lib/python3/dist-packages/sphinx/ext/extlinks.py
/usr/lib/python3/dist-packages/sphinx/ext/graphviz.py
/usr/lib/python3/dist-packages/sphinx/ext/ifconfig.py
/usr/lib/python3/dist-packages/sphinx/ext/inheritance_diagram.py
/usr/lib/python3/dist-packages/sphinx/ext/intersphinx.py
/usr/lib/python3/dist-packages/sphinx/ext/jsmath.py
/usr/lib/python3/dist-packages/sphinx/ext/linkcode.py
/usr/lib/python3/dist-packages/sphinx/ext/mathbase.py
/usr/lib/python3/dist-packages/sphinx/ext/mathjax.py
/usr/lib/python3/dist-packages/sphinx/ext/napoleon/
/usr/lib/python3/dist-packages/sphinx/ext/napoleon/__init__.py
/usr/lib/python3/dist-packages/sphinx/ext/napoleon/docstring.py
/usr/lib/python3/dist-packages/sphinx/ext/napoleon/iterators.py
/usr/lib/python3/dist-packages/sphinx/ext/pngmath.py
/usr/lib/python3/dist-packages/sphinx/ext/todo.py
/usr/lib/python3/dist-packages/sphinx/ext/viewcode.py