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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 kill_all(self):
 """ Kill all currently running jobs. """

        logger.info('Job {0} killing all currently running tasks'.format(self.name))
        for task in self.tasks.itervalues():
            if task.started_at and not task.completed_at:
                task.kill()