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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 _FormatMessageShort(self, event):
 """Formats the short message. Args: event (EventObject):
 event. Returns: str: short message field. Raises: NoFormatterFound: if no event formatter can be found to match the data type in the event. """

    _, message_short = self._output_mediator.GetFormattedMessages(event)
    if message_short is None:
      data_type = getattr(event, 'data_type', 'UNKNOWN')
      raise errors.NoFormatterFound(
          'Unable to find event formatter for: {0:s}.'.format(data_type))

    return message_short