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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 add_aggregated_peak_demand(self):
 """Summarizes peak loads of underlying aggregated load_areas"""

        peak_load_aggregated = 0
        for lv_load_area in self.lv_load_areas():
            if lv_load_area.is_aggregated:
                peak_load_aggregated += lv_load_area.peak_load
        self.peak_load_aggregated = peak_load_aggregated