/usr/lib/python2.7/dist-packages/matplotlib/testing/ is in python-matplotlib 2.1.1-2ubuntu3.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/python2.7/dist-packages/matplotlib/testing/__init__.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/_nose/
/usr/lib/python2.7/dist-packages/matplotlib/testing/_nose/__init__.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/_nose/decorators.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/_nose/exceptions.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/_nose/plugins/
/usr/lib/python2.7/dist-packages/matplotlib/testing/_nose/plugins/__init__.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/_nose/plugins/knownfailure.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/_nose/plugins/performgc.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/compare.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/conftest.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/decorators.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/determinism.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/disable_internet.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/exceptions.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/Duration.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/Epoch.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/EpochConverter.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/StrConverter.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/UnitDbl.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/UnitDblConverter.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/UnitDblFormatter.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/jpl_units/__init__.py
/usr/lib/python2.7/dist-packages/matplotlib/testing/noseclasses.py