/usr/share/emacs/site-lisp/elpa-src/ is in elpa-pdf-tools 0.80-1build1.
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/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-annot.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-cache.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-dev.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-history.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-info.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-isearch.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-links.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-misc.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-occur.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-outline.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-sync.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-tools-autoloads.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-tools-pkg.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-tools.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-util.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-view.el
/usr/share/emacs/site-lisp/elpa-src/pdf-tools-0.80/pdf-virtual.el