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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 ramp(time, slope, start, finish=0):
 """ Implements vensim's and xmile's RAMP function Parameters time: function The current time of modelling slope: float The slope of the ramp starting at zero at time start start: float Time at which the ramp begins finish: float Optional. Time at which the ramp ends Returns ------- response: float If prior to ramp start, returns zero If after ramp ends, returns top of ramp Examples -------- """


    t = time()
    if t < start:
        return 0
    else:
        if finish <= 0:
            return slope * (t - start)
        elif t > finish:
            return slope * (finish - start)
        else:
            return slope * (t - start)