Fix from SF bug #541980 (Jacques A. Vidrine).

When os.stat() for a file raises OSError, turn it into IOError per
documentation.

Bugfix candidate.

Lib/urllib.py

@@ -413,7 +413,10 @@ class URLopener:
         import mimetypes, mimetools, rfc822, StringIO
         host, file = splithost(url)
         localname = url2pathname(file)
+        try:
             stats = os.stat(localname)
+        except OSError, e:
+            raise IOError(e.errno, e.strerror, e.filename)
         size = stats.st_size
         modified = rfc822.formatdate(stats.st_mtime)
         mtype = mimetypes.guess_type(url)[0]