code: def load(cls, data):
          
          if len(data) < cls._PREFIX_SIZE:
              raise ValueError('not enough data to decode UserComment')
          prefix = data[:cls._PREFIX_SIZE]
          body = data[cls._PREFIX_SIZE:]
          if prefix == cls._UNDEFINED_PREFIX:
              raise ValueError('prefix is UNDEFINED, unable to decode UserComment')
          try:
              encoding = {
                  cls._ASCII_PREFIX: cls.ASCII, cls._JIS_PREFIX: cls._JIS, cls._UNICODE_PREFIX: cls._UNICODE,
              }[prefix]
          except KeyError:
              raise ValueError('unable to determine appropriate encoding')
          return body.decode(encoding, errors='replace')
docs: Convert "UserComment" value in exif format to str.
  
          :param bytes data: "UserComment" value from exif
          :return: u"foobar"
          :rtype: str(Unicode)
          :raises: ValueError if the data does not conform to the EXIF specification,
          or the encoding is unsupported.