/usr/share/doc/python3-pyqt5.qtmultimedia-dbg is in python3-pyqt5.qtmultimedia-dbg 5.10.1+dfsg-1ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/python3-pyqt5.qtmultimedia
/usr/share/doc/python3-pyqt5.qtmultimedia