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Ubuntu apt-get can not remove package due to configuration script

I once installed a package (pypy) through apt-get but then recklessly decided to delete the pypy directory (/usr/lib/pypy). When I tried to next do the right thing (sudo apt-get remove pypy) I kept getting funny errors from dpkg. It turned out that there was a script (/var/lib/dpkg/info/pypy.prerm) that dpky was using that was confusing it. Removing this script enabled me to clean out the package and then reinstall it properly.
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