/usr/share/doc/libplplot12/examples/tk/ is in plplot-tcl-dev 5.10.0-0ubuntu5.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/libplplot12/examples/tk/CMakeLists.txt
/usr/share/doc/libplplot12/examples/tk/Makefile
/usr/share/doc/libplplot12/examples/tk/README.tkdemos
/usr/share/doc/libplplot12/examples/tk/plgrid
/usr/share/doc/libplplot12/examples/tk/plgrid.in
/usr/share/doc/libplplot12/examples/tk/plgrid.tcl
/usr/share/doc/libplplot12/examples/tk/plserver_runAllDemos
/usr/share/doc/libplplot12/examples/tk/plserver_runAllDemos.in
/usr/share/doc/libplplot12/examples/tk/plserver_standard_examples
/usr/share/doc/libplplot12/examples/tk/plserver_standard_examples.in
/usr/share/doc/libplplot12/examples/tk/runAllDemos.tcl
/usr/share/doc/libplplot12/examples/tk/runExtendedDemos.tcl
/usr/share/doc/libplplot12/examples/tk/tclIndex
/usr/share/doc/libplplot12/examples/tk/tk01
/usr/share/doc/libplplot12/examples/tk/tk01.in
/usr/share/doc/libplplot12/examples/tk/tk02
/usr/share/doc/libplplot12/examples/tk/tk02.in
/usr/share/doc/libplplot12/examples/tk/tk03
/usr/share/doc/libplplot12/examples/tk/tk03.in
/usr/share/doc/libplplot12/examples/tk/tk04
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/usr/share/doc/libplplot12/examples/tk/tkdemos.tcl
/usr/share/doc/libplplot12/examples/tk/wish_runAllDemos
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/usr/share/doc/libplplot12/examples/tk/wish_standard_examples
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/usr/share/doc/libplplot12/examples/tk/x00.tcl
/usr/share/doc/libplplot12/examples/tk/x01.tcl
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/usr/share/doc/libplplot12/examples/tk/x33.tcl
/usr/share/doc/libplplot12/examples/tk/xtk01.c
/usr/share/doc/libplplot12/examples/tk/xtk02.c
/usr/share/doc/libplplot12/examples/tk/xtk04.c