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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_extra_data(cls, data):
 """Loads extra JSON configuration parameters from a data buffer. The data buffer must represent a JSON object. Args: data: str, the buffer to load the JSON data from. """

    try:
      cls._extra_config.update(json.loads(data))
    except ValueError as exception:
      sys.stderr.write('Could convert to JSON. {0:s}'.format(exception))
      exit(-1)