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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 _countdown(seconds):
 """ Wait `seconds` counting down. """

    for i in range(seconds, 0, -1):
        sys.stdout.write("%02d" % i)
        time.sleep(1)
        sys.stdout.write("\b\b")
        sys.stdout.flush()
    sys.stdout.flush()