/usr/lib/python3/dist-packages/ginga/gtk3w/ is in python3-ginga 2.6.1-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/python3/dist-packages/ginga/gtk3w/GtkHelp.py
/usr/lib/python3/dist-packages/ginga/gtk3w/ImageViewCanvasGtk.py
/usr/lib/python3/dist-packages/ginga/gtk3w/ImageViewCanvasTypesGtk.py
/usr/lib/python3/dist-packages/ginga/gtk3w/ImageViewGtk.py
/usr/lib/python3/dist-packages/ginga/gtk3w/Plot.py
/usr/lib/python3/dist-packages/ginga/gtk3w/Viewers.py
/usr/lib/python3/dist-packages/ginga/gtk3w/Widgets.py
/usr/lib/python3/dist-packages/ginga/gtk3w/__init__.py
/usr/lib/python3/dist-packages/ginga/gtk3w/gtk_css
/usr/lib/python3/dist-packages/ginga/gtk3w/plugins/
/usr/lib/python3/dist-packages/ginga/gtk3w/plugins/WBrowser.py
/usr/lib/python3/dist-packages/ginga/gtk3w/plugins/__init__.py
/usr/lib/python3/dist-packages/ginga/gtk3w/setup_package.py