145 

   146 def normasprefix(path):

   147     '''normalize the specified path as path prefix

   148 

   149     Returned vaule can be used safely for "p.startswith(prefix)",

   150     "p[len(prefix):]", and so on.

   151 

   152     For efficiency, this expects "path" argument to be already

   153     normalized by "os.path.normpath", "os.path.realpath", and so on.

   154 

   155     See also issue3033 for detail about need of this function.

   156 

   157     >>> normasprefix('/foo/bar').replace(os.sep, '/')

   158     '/foo/bar/'

   159     >>> normasprefix('/').replace(os.sep, '/')

   160     '/'

   161     '''

   162     d, p = os.path.splitdrive(path)

   163     if len(p) != len(os.sep):

   164         return path + os.sep

   165     else:

   166         return path