/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/ is in python-sagenb 1.0.1+ds1-2.
This file is owned by root:root, with mode 0o755.
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/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/async_lib.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/canvas3d_lib.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/debug.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/jmol_lib.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/localization.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/master.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/mathjax_sage.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/notebook_dynamic.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/notebook_lib.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/published_worksheet.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/tinymce.js
/usr/lib/python2.7/dist-packages/sagenb/data/sage/js/ws_list.js