Python os.stat and unicode file names

In my Django application, a user has uploaded a file with a unicode character in the name.

When I'm downloading files, I'm calling :

os.path.exists(media)

to test that the file is there. This, in turn, seems to call

st = os.stat(path)

Which then blows up with the error :

UnicodeEncodeError: 'ascii' codec can't encode character u'\xcf' in position 92: ordinal not in range(128)

What can I do about this? Is there an option to path.exists to handle it?

Update : Actually, all I had to do was encode the argument to exists, ie.

os.path.exists(media.encode('utf-8')

Thanks everyone who answered.