/usr/lib/python3/dist-packages/matplotlib/testing/ is in python3-matplotlib 1.3.1-1ubuntu5.
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/usr/lib/python3/dist-packages/matplotlib/testing/__init__.py
/usr/lib/python3/dist-packages/matplotlib/testing/compare.py
/usr/lib/python3/dist-packages/matplotlib/testing/decorators.py
/usr/lib/python3/dist-packages/matplotlib/testing/image_util.py
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/Duration.py
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/Epoch.py
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/EpochConverter.py
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/StrConverter.py
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/UnitDbl.py
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/UnitDblConverter.py
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/UnitDblFormatter.py
/usr/lib/python3/dist-packages/matplotlib/testing/jpl_units/__init__.py
/usr/lib/python3/dist-packages/matplotlib/testing/noseclasses.py