/usr/lib/ is in python3-serial 2.5-2.1build1.
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/usr/lib/python3/
/usr/lib/python3/dist-packages/
/usr/lib/python3/dist-packages/pyserial-2.5.egg-info
/usr/lib/python3/dist-packages/serial/
/usr/lib/python3/dist-packages/serial/serialwin32.py
/usr/lib/python3/dist-packages/serial/serialposix.py
/usr/lib/python3/dist-packages/serial/loopback_connection.py
/usr/lib/python3/dist-packages/serial/serialcli.py
/usr/lib/python3/dist-packages/serial/serialutil.py
/usr/lib/python3/dist-packages/serial/rfc2217.py
/usr/lib/python3/dist-packages/serial/__init__.py
/usr/lib/python3/dist-packages/serial/win32.py
/usr/lib/python3/dist-packages/serial/socket_connection.py
/usr/lib/python3/dist-packages/serial/sermsdos.py
/usr/lib/python3/dist-packages/serial/serialjava.py