Problem
1. Write a script that accepts a compressed filename as argument (which could be .gz, .bz2 or .zip). It looks at the extension and decompresses the file using the correct decompression program, but only if the decompressed file (or one with the same name) doesn't exist.
2. Devise a script that accepts two directory names, bar1 and bar2, and deletes those files in bar2 which are identical to their namesakes in bar1.