The fix for this issue broke support for bytes in shutil.rmtree:

$ mkdir -p /tmp/a/b
$ python3.2 -c 'import shutil; shutil.rmtree(b"/tmp/a")'
$ mkdir -p /tmp/a/b
$ python3.3 -c 'import shutil; shutil.rmtree(b"/tmp/a")'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib64/python3.3/shutil.py", line 444, in rmtree
    _rmtree_safe_fd(fd, path, onerror)
  File "/usr/lib64/python3.3/shutil.py", line 381, in _rmtree_safe_fd
    fullname = os.path.join(path, name)
  File "/usr/lib64/python3.3/posixpath.py", line 78, in join
    if b.startswith(sep):
TypeError: startswith first arg must be str or a tuple of str, not bytes
$