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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 pulse_train(time, start, duration, repeat_time, end):
 """ Implements vensim's PULSE TRAIN function In range [-inf, start) returns 0 In range [start + n * repeat_time, start + n * repeat_time + duration) return 1 In range [start + n * repeat_time + duration, start + (n+1) * repeat_time) return 0 """

    t = time()
    if start <= t < end:
        return 1 if (t - start) % repeat_time < duration else 0
    else:
        return 0