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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 flush(self):
 """ Flush the buffer of buffered tiers to our destination tiers. """

        if self.buffer is None:
            return
        data = self.buffer
        self.buffer = []
        for x in self.dests:
            yield from x.enqueue_task(self, *data)