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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(time, start, duration):
 """ Implements vensim's PULSE function In range [-inf, start) returns 0 In range [start, start + duration) returns 1 In range [start + duration, +inf] returns 0 """

    t = time()
    return 1 if start <= t < start + duration else 0