code: def rel_path(anchor, *paths):
      
      anchor = os.path.abspath(os.path.expandvars(os.path.expanduser(anchor)))
      if os.path.exists(anchor) and os.path.isfile(anchor):
          anchor = os.path.dirname(anchor)
      return os.path.normpath(os.path.join(anchor, *paths))
docs: Returns a path made of framgment *paths* relativ to an *anchor* path. When *anchor* is a file,
      its absolute directory is used instead.