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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 exponential_size_change(Nstart, Nstop, time):
 """ Generate a list of population sizes according to exponential size_change model :param Nstart: population size at onset of size change :param Nstop: Population size to reach at end of size change :param time: Time (in generations) to get from Nstart to Nstop :return: A list of integers representing population size over time. .. versionadded:: 0.1.1 """

    if time < 1:
        raise RuntimeError("time must be >= 1")
    if Nstart < 1 or Nstop < 1:
        raise RuntimeError("Nstart and Nstop must both be >= 1")
    G = math.exp((math.log(Nstop) - math.log(Nstart))/time)
    rv = []
    for i in range(time):
        rv.append(round(Nstart*pow(G, i+1)))
    return rv