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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 get_time_objects_from_model_timesteps(cls, times, start):
 """ Calculate the datetimes of the model timesteps times should start at 0 and be in seconds """

        modelTimestep = []
        newtimes = []

        for i in xrange(0, len(times)):
            try:
                modelTimestep.append(times[i+1] - times[i])
            except StandardError:
                modelTimestep.append(times[i] - times[i-1])
            newtimes.append(start + timedelta(seconds=times[i]))
      
        return (modelTimestep, newtimes)