/usr/share/wordpress/wp-content/themes/ is in wordpress-theme-twentyfifteen 4.9.5+dfsg1-1.
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/usr/share/wordpress/wp-content/themes/twentyfifteen/
/usr/share/wordpress/wp-content/themes/twentyfifteen/404.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/archive.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/author-bio.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/comments.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/content-link.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/content-none.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/content-page.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/content-search.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/content.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/css/
/usr/share/wordpress/wp-content/themes/twentyfifteen/css/editor-style.css
/usr/share/wordpress/wp-content/themes/twentyfifteen/css/ie.css
/usr/share/wordpress/wp-content/themes/twentyfifteen/css/ie7.css
/usr/share/wordpress/wp-content/themes/twentyfifteen/footer.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/functions.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/genericons/
/usr/share/wordpress/wp-content/themes/twentyfifteen/genericons/Genericons.eot
/usr/share/wordpress/wp-content/themes/twentyfifteen/genericons/Genericons.svg
/usr/share/wordpress/wp-content/themes/twentyfifteen/genericons/Genericons.ttf
/usr/share/wordpress/wp-content/themes/twentyfifteen/genericons/Genericons.woff
/usr/share/wordpress/wp-content/themes/twentyfifteen/genericons/README.md
/usr/share/wordpress/wp-content/themes/twentyfifteen/genericons/genericons.css
/usr/share/wordpress/wp-content/themes/twentyfifteen/header.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/image.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/inc/
/usr/share/wordpress/wp-content/themes/twentyfifteen/inc/back-compat.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/inc/custom-header.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/inc/customizer.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/inc/template-tags.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/index.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/js/
/usr/share/wordpress/wp-content/themes/twentyfifteen/js/color-scheme-control.js
/usr/share/wordpress/wp-content/themes/twentyfifteen/js/customize-preview.js
/usr/share/wordpress/wp-content/themes/twentyfifteen/js/functions.js
/usr/share/wordpress/wp-content/themes/twentyfifteen/js/html5.js
/usr/share/wordpress/wp-content/themes/twentyfifteen/js/keyboard-image-navigation.js
/usr/share/wordpress/wp-content/themes/twentyfifteen/js/skip-link-focus-fix.js
/usr/share/wordpress/wp-content/themes/twentyfifteen/page.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/readme.txt
/usr/share/wordpress/wp-content/themes/twentyfifteen/rtl.css
/usr/share/wordpress/wp-content/themes/twentyfifteen/screenshot.png
/usr/share/wordpress/wp-content/themes/twentyfifteen/search.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/sidebar.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/single.php
/usr/share/wordpress/wp-content/themes/twentyfifteen/style.css