/usr/lib/ghc-doc/hoogle/data-accessor-template.txt is in libghc-data-accessor-template-doc 0.2.1.10-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-data-accessor-template-doc/html/data-accessor-template.txt