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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 WriteEventMACBGroup(self, event_macb_group):
 """Writes an event MACB group to the output. Args: event_macb_group (list[EventObject]):
 event MACB group. """

    output_values = self._GetOutputValues(event_macb_group[0])

    timestamp_descriptions = [
        event.timestamp_desc for event in event_macb_group]
    output_values[3] = (
        self._output_mediator.GetMACBRepresentationFromDescriptions(
            timestamp_descriptions))
    # TODO: fix timestamp description in source.
    output_values[6] = '; '.join(timestamp_descriptions)

    self._WriteOutputValues(output_values)