/etc/piuparts/ is in piuparts 0.77.
This file is owned by root:root, with mode 0o755.
..
/etc/piuparts/scripts/
/etc/piuparts/scripts-apt-first/
/etc/piuparts/scripts-apt-first/pre_distupgrade_zz_apt_first
/etc/piuparts/scripts-debug-packagemanager/
/etc/piuparts/scripts-debug-packagemanager/pre_distupgrade_debug_packagemanager
/etc/piuparts/scripts-debug-problemresolver/
/etc/piuparts/scripts-debug-problemresolver/pre_distupgrade_debug_problemresolver
/etc/piuparts/scripts-debug-problemresolver/pre_install_debug_problemresolver
/etc/piuparts/scripts-debug-purge/
/etc/piuparts/scripts-debug-purge/post_remove_postrm_set-x
/etc/piuparts/scripts-debug-remove/
/etc/piuparts/scripts-debug-remove/pre_remove_prerm_postrm_set-x
/etc/piuparts/scripts-jessie/
/etc/piuparts/scripts-jessie/post_setup_jessie-fake-essential
/etc/piuparts/scripts-leftovers/
/etc/piuparts/scripts-leftovers/post_purge_manual_cleanup
/etc/piuparts/scripts-leftovers/post_remove_cleanup
/etc/piuparts/scripts-leftovers/post_setup_fake-essential
/etc/piuparts/scripts-leftovers/pre_remove_preseed_cleanup
/etc/piuparts/scripts-log-alternatives/
/etc/piuparts/scripts-log-alternatives/post_install_log_alternatives
/etc/piuparts/scripts-log-alternatives/pre_install_log_alternatives
/etc/piuparts/scripts-no-usr-share-doc/
/etc/piuparts/scripts-no-usr-share-doc/post_setup_disable_usr_share_doc
/etc/piuparts/scripts-squeeze/
/etc/piuparts/scripts-squeeze/post_distupgrade_squeeze-fake-essential
/etc/piuparts/scripts-squeeze/post_remove_exceptions_lenny
/etc/piuparts/scripts-squeeze/post_remove_exceptions_squeeze
/etc/piuparts/scripts-squeeze/post_setup_squeeze-fake-essential
/etc/piuparts/scripts-sysvinit/
/etc/piuparts/scripts-sysvinit/pre_distupgrade_zz_sysvinit
/etc/piuparts/scripts-unused-examples/
/etc/piuparts/scripts-unused-examples/post_chroot_unpack_key_setup
/etc/piuparts/scripts-wheezy/
/etc/piuparts/scripts-wheezy/post_setup_wheezy-fake-essential
/etc/piuparts/scripts-wheezy/pre_distupgrade_wheezy
/etc/piuparts/scripts/is_testable_uninstallable
/etc/piuparts/scripts/post_distupgrade_base_cleanup
/etc/piuparts/scripts/post_distupgrade_exceptions
/etc/piuparts/scripts/post_distupgrade_force-unsafe-io
/etc/piuparts/scripts/post_distupgrade_squeeze-backports
/etc/piuparts/scripts/post_install_exceptions
/etc/piuparts/scripts/post_purge_exceptions
/etc/piuparts/scripts/post_remove_exceptions
/etc/piuparts/scripts/post_setup_dummy_users
/etc/piuparts/scripts/post_setup_forbid_home
/etc/piuparts/scripts/post_setup_force-unsafe-io
/etc/piuparts/scripts/post_setup_minimize
/etc/piuparts/scripts/post_setup_squeeze-backports
/etc/piuparts/scripts/pre_distupgrade_exceptions
/etc/piuparts/scripts/pre_distupgrade_foreign_architecture_i386
/etc/piuparts/scripts/pre_distupgrade_zz_database-server
/etc/piuparts/scripts/pre_distupgrade_zz_upgrade_early
/etc/piuparts/scripts/pre_install_database-server
/etc/piuparts/scripts/pre_install_exceptions
/etc/piuparts/scripts/pre_install_extras
/etc/piuparts/scripts/pre_install_foreign_architecture
/etc/piuparts/scripts/pre_install_foreign_architecture_i386
/etc/piuparts/scripts/pre_remove_40_find_missing_md5sums
/etc/piuparts/scripts/pre_remove_40_find_obsolete_conffiles
/etc/piuparts/scripts/pre_remove_40_find_unowned_lib_links
/etc/piuparts/scripts/pre_remove_50_find_bad_permissions
/etc/piuparts/scripts/pre_remove_50_find_missing_copyright
/etc/piuparts/scripts/pre_remove_exceptions
/etc/piuparts/scripts/pre_test_root_password