Revert incorrect commit 9351edad48523bb38b1bf651506786bdc8814f62, which broke file type detection
in chpathtool.py with Python 3 and magic module present.

>>> import magic
>>> m = magic.open(magic.MIME_TYPE)
>>> m.load()
0
>>> m.file(b"/etc/fstab")
'text/plain'
>>> m.file(str(b"/etc/fstab"))
"cannot open `b'/etc/fstab'' (No such file or directory)"
1 file changed