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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 promise(cls, fn, *args, **kwargs):
 """ Used to build a task based on a callable function and the arguments. Kick it off and start execution of the task. :param fn: callable :param args: tuple :param kwargs: dict :return: SynchronousTask or AsynchronousTask """

        task = cls.task(target=fn, args=args, kwargs=kwargs)
        task.start()
        return task