/usr/lib/python3.5/turtledemo/ is in python3.5-examples 3.5.3-1+deb9u1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/python3.5/turtledemo/__init__.py
/usr/lib/python3.5/turtledemo/__main__.py
/usr/lib/python3.5/turtledemo/bytedesign.py
/usr/lib/python3.5/turtledemo/chaos.py
/usr/lib/python3.5/turtledemo/clock.py
/usr/lib/python3.5/turtledemo/colormixer.py
/usr/lib/python3.5/turtledemo/forest.py
/usr/lib/python3.5/turtledemo/fractalcurves.py
/usr/lib/python3.5/turtledemo/lindenmayer.py
/usr/lib/python3.5/turtledemo/minimal_hanoi.py
/usr/lib/python3.5/turtledemo/nim.py
/usr/lib/python3.5/turtledemo/paint.py
/usr/lib/python3.5/turtledemo/peace.py
/usr/lib/python3.5/turtledemo/penrose.py
/usr/lib/python3.5/turtledemo/planet_and_moon.py
/usr/lib/python3.5/turtledemo/round_dance.py
/usr/lib/python3.5/turtledemo/sorting_animate.py
/usr/lib/python3.5/turtledemo/tree.py
/usr/lib/python3.5/turtledemo/turtle.cfg
/usr/lib/python3.5/turtledemo/two_canvases.py
/usr/lib/python3.5/turtledemo/wikipedia.py
/usr/lib/python3.5/turtledemo/yinyang.py