'charmap' codec can't decode byte 0x9d in position 154: character maps to <undefined>


Traceback (most recent call last):
  File "/mnt/hd/web/1bpm.net/ml.csound/app/handler.py", line 386, in <module>
    handle()
  File "/mnt/hd/web/1bpm.net/ml.csound/app/handler.py", line 373, in handle
    return Thread(mailing_list).render({"threadid": int(parts[2])})
  File "/mnt/hd/web/1bpm.net/ml.csound/app/handler.py", line 203, in render
    self.create(data)
  File "/mnt/hd/web/1bpm.net/ml.csound/app/handler.py", line 275, in create
    content += msg.html
  File "/mnt/hd/web/1bpm.net/ml.csound/app/handler.py", line 154, in html
    if len(self.article.attachments) > 0:
  File "/mnt/hd/web/1bpm.net/ml.csound/app/handler.py", line 144, in article
    self.parsed_article = ParsedMessage(msg)
  File "/mnt/hd/web/1bpm.net/ml.csound/app/handler.py", line 39, in __init__
    self.parse(msg)
  File "/mnt/hd/web/1bpm.net/ml.csound/app/handler.py", line 76, in parse
    self.text += part.get_payload(decode=True).decode(charset)
  File "/usr/lib/python2.7/encodings/cp1252.py", line 15, in decode
    return codecs.charmap_decode(input,errors,decoding_table)
UnicodeDecodeError: 'charmap' codec can't decode byte 0x9d in position 154: character maps to <undefined>