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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 launch_next(self, task=None, result=None):
 """ Launch next task or finish operation :param kser.sequencing.task.Task task: previous task :param cdumay_result.Result result: previous task result :return: Execution result :rtype: cdumay_result.Result """

        if task:
            next_task = self.next(task)
            if next_task:
                return next_task.send(result=result)
            else:
                return self.set_status(task.status, result)
        elif len(self.tasks) > 0:
            return self.tasks[0].send(result=result)
        else:
            return Result(retcode=1, stderr="Nothing to do, empty operation !")