Merge two directories together

[Keith Hughitt]

Suppose you have two file-trees with common sub-directories but
different files that you want to merge together, e.g.

/test/
/test/a/
/test/a/file1

/test2/
/test2/a/
/test2/a/file2

You can easily merge the directories in Linux using the "cp" command:

cp -r test/* test2/

While Python provides some helpful methods for moving files and
directories around (shutil.move, shutil.copytree, etc), none of them
seem to be able to merge two directories.

I've looked around some on Google for an alternative to calling cp
directly, but so far no luck.

Any ideas?