Sjoerd Mullender:

In splithost, accept empty host part in URLs.  This is required for
file URLs that can have an empty host part.  For such URLs, we should
not return the initial 2 slashes as part of the file name.

Lib/urllib.py

@@ -773,7 +773,7 @@ def splithost(url):
     global _hostprog
     if _hostprog is None:
         import re
-        _hostprog = re.compile('^//([^/]+)(.*)$')
+        _hostprog = re.compile('^//([^/]*)(.*)$')
 
     match = _hostprog.match(url) 
     if match: return match.group(1, 2)