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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 on_finished(self):
 """Finished signal handler"""

        self.controller.is_running = False

        error = self.controller.current_error
        if error is not None:
            self.info(self.tr("Stopped due to error(s), see Terminal."))
        else:
            self.info(self.tr("Finished successfully!"))