/usr/lib/pyshared/python2.6/_mysql.so is in python-mysqldb 1.2.3-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/pyshared/python2.6/../../python2.6/dist-packages/_mysql.so
/usr/lib/pyshared/python2.6/../../python2.6/dist-packages/_mysql.so