Milky Way Traceback

D:\Golfing\Milky-Way-master>C:\Python34\python.exe mw descending_digits.mwg -i 5
Traceback (most recent call last):
  File "mw", line 41, in <module>
    MilkyWay(program)
  File "mw", line 15, in __init__
    standard.Standard.__init__(self, program, pre_stack, specVals)
  File "D:\Golfing\Milky-Way-master\standard.py", line 126, in __init__
    base.Base.__init__(self, program, pre_stack)
  File "D:\Golfing\Milky-Way-master\base.py", line 62, in __init__
    self.stack = self.tokenize(program)
  File "D:\Golfing\Milky-Way-master\base.py", line 128, in tokenize
    raise errors.UnknownOpcode(j)
errors.UnknownOpcode: 'ï' is not a valid opcode.