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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 await_flush_completion(self, timeout=None):
 """ Mark all partitions as ready to send and block until the send is complete """

        try:
            for batch in self._incomplete.all():
                log.debug('Waiting on produce to %s',
                          batch.produce_future.topic_partition)
                if not batch.produce_future.wait(timeout=timeout):
                    raise Errors.KafkaTimeoutError('Timeout waiting for future')
                if not batch.produce_future.is_done:
                    raise Errors.UnknownError('Future not done')

                if batch.produce_future.failed():
                    log.warning(batch.produce_future.exception)
        finally:
            self._flushes_in_progress.decrement()