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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 _internal_reschedule(callback, retry=3, sleep_time=constants.DEFAULT_SLEEP):
 """ workaround method for internal_run_container method It sometimes fails because of Dbus or whatever, so try to start it moretimes :param callback: callback method list :param retry: how many times try to invoke command :param sleep_time: how long wait before subprocess.poll() to find if it failed :return: subprocess object """

        for foo in range(retry):
            container_process = callback[0](callback[1], *callback[2], **callback[3])
            time.sleep(sleep_time)
            container_process.poll()
            rcode = container_process.returncode
            if rcode is None:
                return container_process
        raise ConuException("Unable to start nspawn container - process failed for {}-times".format(retry))