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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 _GetMessage(self, event_object):
 """Returns a properly formatted message string. Args: event_object: the event object (instance od EventObject). Returns: A formatted message string. """

    # TODO: move this somewhere where the mediator can be instantiated once.
    formatter_mediator = formatters_mediator.FormatterMediator()

    result = ''
    try:
      result, _ = formatters_manager.FormattersManager.GetMessageStrings(
          formatter_mediator, event_object)
    except KeyError as exception:
      logging.warning(
          'Unable to correctly assemble event with error: {0!s}'.format(
              exception))

    return result