/usr/share/doc/python3-sunlight/rst is in python-sunlight-doc 1.1.5-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/python3-sunlight/../python-sunlight-doc/html/_sources
/usr/share/doc/python3-sunlight/../python-sunlight-doc/html/_sources