/usr/lib/python3/dist-packages/flask/ is in python3-flask 0.10.1-2.
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/usr/lib/python3/dist-packages/flask/__init__.py
/usr/lib/python3/dist-packages/flask/_compat.py
/usr/lib/python3/dist-packages/flask/app.py
/usr/lib/python3/dist-packages/flask/blueprints.py
/usr/lib/python3/dist-packages/flask/config.py
/usr/lib/python3/dist-packages/flask/ctx.py
/usr/lib/python3/dist-packages/flask/debughelpers.py
/usr/lib/python3/dist-packages/flask/ext/
/usr/lib/python3/dist-packages/flask/ext/__init__.py
/usr/lib/python3/dist-packages/flask/exthook.py
/usr/lib/python3/dist-packages/flask/globals.py
/usr/lib/python3/dist-packages/flask/helpers.py
/usr/lib/python3/dist-packages/flask/json.py
/usr/lib/python3/dist-packages/flask/logging.py
/usr/lib/python3/dist-packages/flask/module.py
/usr/lib/python3/dist-packages/flask/sessions.py
/usr/lib/python3/dist-packages/flask/signals.py
/usr/lib/python3/dist-packages/flask/templating.py
/usr/lib/python3/dist-packages/flask/testing.py
/usr/lib/python3/dist-packages/flask/views.py
/usr/lib/python3/dist-packages/flask/wrappers.py