code: def peak_generation(self, mode):
          
  
          if mode == 'MV':
              return sum([_.capacity for _ in self.grid.generators()])
  
          elif mode == 'MVLV':
              # calc MV geno capacities
              cum_mv_peak_generation = sum([_.capacity for _ in self.grid.generators()])
              # calc LV geno capacities
              cum_lv_peak_generation = 0
              for load_area in self.grid.grid_district.lv_load_areas():
                  cum_lv_peak_generation += load_area.peak_generation
  
              return cum_mv_peak_generation + cum_lv_peak_generation
  
          else:
              raise ValueError('parameter \'mode\' is invalid!')
docs: Calculates cumulative peak generation of generators connected to underlying grids
          
          This is done instantaneously using bottom-up approach.
  
          Parameters
          ----------
          mode: str
              determines which generators are included::
  
              'MV':   Only generation capacities of MV level are considered.
              
              'MVLV': Generation capacities of MV and LV are considered
                      (= cumulative generation capacities in entire MVGD).
  
          Returns
          -------
          float
              Cumulative peak generation