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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 sleep(dt):
 """Public function to sleep some time. Example: yield tasklets.sleep(0.5) # Sleep for half a sec. """

  fut = Future('sleep(%.3f)' % dt)
  eventloop.queue_call(dt, fut.set_result, None)
  return fut