SF patch #461781 by Chris Lawrence: os.path.realpath - Resolve symlinks:

Once upon a time, I put together a little function
   that tries to find the canonical filename for a given
   pathname on POSIX. I've finally gotten around to
   turning it into a proper patch with documentation.
   On non-POSIX, I made it an alias for 'abspath', as
   that's the behavior on POSIX when no symlinks are
   encountered in the path.

   Example:
   >>> os.path.realpath('/usr/bin/X11/X')
   '/usr/X11R6/bin/X'

Lib/macpath.py

@@ -225,3 +225,6 @@ def abspath(path):
     if not isabs(path):
         path = join(os.getcwd(), path)
     return normpath(path)
+
+# realpath is a no-op on systems without islink support
+realpath = abspath