How can files be added to a tarfile with Python, without adding the directory hierarchy?

Using the arcname argument of TarFile.add() method is an alternate and convenient way to match your destination.

Example: you want to archive a dir repo/a.git/ to a tar.gz file, but you rather want the tree root in the archive begins by a.git/ but not repo/a.git/, you can do like followings:

archive = tarfile.open("a.git.tar.gz", "w|gz")
archive.add("repo/a.git", arcname="a.git")
archive.close()