Issue 8463: shutil.make_archive() supports bz2, but it's not documented (original) (raw)
Seems like these formats are supported, so yes "bztar" can be used as a format parameter.
_ARCHIVE_FORMATS = {
'gztar': (_make_tarball, [('compress', 'gzip')], "gzip'ed tar-file"),
'bztar': (_make_tarball, [('compress', 'bzip2')], "bzip2'ed tar-file"),
'ztar': (_make_tarball, [('compress', 'compress')],
"compressed tar file"),
'tar': (_make_tarball, [('compress', None)], "uncompressed tar file"),
'zip': (_make_zipfile, [],"ZIP file")
}