/usr/lib/python2.7/dist-packages/IPython/frontend/html/notebook/static/codemirror/theme/ is in ipython-notebook 0.12.1+dfsg-0ubuntu1.
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/usr/lib/python2.7/dist-packages/IPython/frontend/html/notebook/static/codemirror/theme/default.css
/usr/lib/python2.7/dist-packages/IPython/frontend/html/notebook/static/codemirror/theme/elegant.css
/usr/lib/python2.7/dist-packages/IPython/frontend/html/notebook/static/codemirror/theme/ipython.css
/usr/lib/python2.7/dist-packages/IPython/frontend/html/notebook/static/codemirror/theme/neat.css
/usr/lib/python2.7/dist-packages/IPython/frontend/html/notebook/static/codemirror/theme/night.css