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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 fatal(self, msg, exc=None):
 """ Exit on a fatal error. """

        if exc is not None:
            self.LOG.fatal("%s (%s)" % (msg, exc))
            if self.options.debug:
                return # let the caller re-raise it
        else:
            self.LOG.fatal(msg)
        sys.exit(error.EX_SOFTWARE)