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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 run(self, stop):
 """ Run the pipeline. :param stop: Stop event """

        _LOGGER.info("Starting a new pipeline on group %s", self._group)
        self._group.bridge.incr_active()
        for i, stage in enumerate(self._pipe):
            self._execute_stage(i, stage, stop)
        _LOGGER.info("Finished pipeline on group %s", self._group)
        self._group.bridge.decr_active()