leftover pyc files

[Andrea Crotti]

In our current setup, the script in charge to run our applications also
scan all the directories and if it finds any "pyc" file without the 
corresponding
module, it removes it.

This was done because when you rename something, the old "pyc" remains
there and can cause problems.

Is it the only way possible to scan through and remove all of them or is
there a smarter way?