docs: def unhex(inp):
      '''unquote(r'abc\x20def') -> 'abc def'.'''
      res = inp.split(r'\x')
      for i in xrange(1, len(res)):
          item = res[i]
          try:
              res[i] = _hextochr[item[:2]] + item[2:]
          except KeyError:
              res[i] = '%' + item
          except UnicodeDecodeError:
              res[i] = unichr(int(item[:2], 16)) + item[2:]
      return ''.join(res)