/usr/share/doc/python3-checkbox-ng-doc/html/_static/doctools.js is in python3-checkbox-ng-doc 0.3.1-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/python3-checkbox-ng-doc/html/_static/../../../../javascript/sphinxdoc/1.0/doctools.js