/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/ is in python3-plainbox 0.25-1.
This file is owned by root:root, with mode 0o755.
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/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/jobs/
/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/jobs/categories.pxu
/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/jobs/local.pxu
/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/jobs/multilevel.pxu
/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/jobs/representative.pxu
/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/jobs/stub.pxu
/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/jobs/win.pxu
/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/testplans/
/usr/lib/python3/dist-packages/plainbox/impl/providers/stubbox/units/testplans/all.pxu