code: def _(path):
      
      if path is None:
          return u("")
      if not PY3:
          if type(path) == unicode:
              return path
          try:
              return _decode_utf8(path)
          except UnicodeDecodeError:
              pass
      return path
docs: Normalize path to unicode
      :param path: path
      :return: normalize path
  
      >>> _(None)
      u''
      >>> _(u("test1"))
      u'test1'
      >>> _("test2")
      u'test2'