/usr/lib/python3/dist-packages/ffc/backends/ is in python3-ffc 2017.2.0.post0-2.
This file is owned by root:root, with mode 0o755.
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/usr/lib/python3/dist-packages/ffc/backends/__init__.py
/usr/lib/python3/dist-packages/ffc/backends/dolfin/
/usr/lib/python3/dist-packages/ffc/backends/dolfin/__init__.py
/usr/lib/python3/dist-packages/ffc/backends/dolfin/capsules.py
/usr/lib/python3/dist-packages/ffc/backends/dolfin/form.py
/usr/lib/python3/dist-packages/ffc/backends/dolfin/functionspace.py
/usr/lib/python3/dist-packages/ffc/backends/dolfin/goalfunctional.py
/usr/lib/python3/dist-packages/ffc/backends/dolfin/includes.py
/usr/lib/python3/dist-packages/ffc/backends/dolfin/wrappers.py
/usr/lib/python3/dist-packages/ffc/backends/ufc/
/usr/lib/python3/dist-packages/ffc/backends/ufc/__init__.py
/usr/lib/python3/dist-packages/ffc/backends/ufc/coordinate_mapping.py
/usr/lib/python3/dist-packages/ffc/backends/ufc/dofmap.py
/usr/lib/python3/dist-packages/ffc/backends/ufc/finite_element.py
/usr/lib/python3/dist-packages/ffc/backends/ufc/form.py
/usr/lib/python3/dist-packages/ffc/backends/ufc/function.py
/usr/lib/python3/dist-packages/ffc/backends/ufc/integrals.py
/usr/lib/python3/dist-packages/ffc/backends/ufc/ufc.h
/usr/lib/python3/dist-packages/ffc/backends/ufc/ufc_geometry.h