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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 elapsed(t0=0.0):
 """get elapsed time from the give time Returns: now: the absolute time now dt_str: elapsed time in string """

    now = time()
    dt = now - t0
    dt_sec = Decimal(str(dt)).quantize(Decimal('.0001'), rounding=ROUND_DOWN)
    if dt_sec <= 1:
        dt_str = str(dt_sec) + ' second'
    else:
        dt_str = str(dt_sec) + ' seconds'
    return now, dt_str