/usr/share/sigil/plugin_launchers/ is in sigil-data 0.9.9+dfsg-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/sigil/plugin_launchers/python/
/usr/share/sigil/plugin_launchers/python/bookcontainer.py
/usr/share/sigil/plugin_launchers/python/compatibility_utils.py
/usr/share/sigil/plugin_launchers/python/epub_utils.py
/usr/share/sigil/plugin_launchers/python/inputcontainer.py
/usr/share/sigil/plugin_launchers/python/launcher.py
/usr/share/sigil/plugin_launchers/python/opf_parser.py
/usr/share/sigil/plugin_launchers/python/outputcontainer.py
/usr/share/sigil/plugin_launchers/python/pluginhunspell.py
/usr/share/sigil/plugin_launchers/python/preferences.py
/usr/share/sigil/plugin_launchers/python/quickparser.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/
/usr/share/sigil/plugin_launchers/python/sigil_bs4/AUTHORS.txt
/usr/share/sigil/plugin_launchers/python/sigil_bs4/__init__.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/builder/
/usr/share/sigil/plugin_launchers/python/sigil_bs4/builder/__init__.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/builder/_html5lib.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/builder/_htmlparser.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/builder/_lxml.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/dammit.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/diagnose.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/element.py
/usr/share/sigil/plugin_launchers/python/sigil_bs4/sigil_custom_changes_to_bs4-4.4.0.patch.txt
/usr/share/sigil/plugin_launchers/python/sigil_gumbo_bs4_adapter.py
/usr/share/sigil/plugin_launchers/python/sigil_gumboc.py
/usr/share/sigil/plugin_launchers/python/sigil_gumboc_tags.py
/usr/share/sigil/plugin_launchers/python/unipath.py
/usr/share/sigil/plugin_launchers/python/validationcontainer.py
/usr/share/sigil/plugin_launchers/python/validationresult.py
/usr/share/sigil/plugin_launchers/python/wrapper.py