docs: def ramp_limits(network):
      """ Add ramping constraints to thermal power plants.
  
      Parameters
      ----------
      network : :class:`pypsa.Network
          Overall container of PyPSA
  
      Returns
      -------
      
      """
      carrier = ['coal', 'biomass', 'gas', 'oil', 'waste', 'lignite',
                         'uranium', 'geothermal']
      data = {'start_up_cost':[77, 57, 42, 57, 57, 77, 50, 57], #€/MW
              'start_up_fuel':[4.3, 2.8, 1.45, 2.8, 2.8, 4.3, 16.7, 2.8], #MWh/MW
              'min_up_time':[5, 2, 3, 2, 2, 5, 12, 2], 
              'min_down_time':[7, 2, 2, 2, 2, 7, 17, 2], 
  # =============================================================================
  #             'ramp_limit_start_up':[0.4, 0.4, 0.4, 0.4, 0.4, 0.6, 0.5, 0.4], 
  #             'ramp_limit_shut_down':[0.4, 0.4, 0.4, 0.4, 0.4, 0.6, 0.5, 0.4] 
  # =============================================================================
              'p_min_pu':[0.33, 0.38, 0.4, 0.38, 0.38, 0.5, 0.45, 0.38]
              }
      df = pd.DataFrame(data, index=carrier)
      fuel_costs = network.generators.marginal_cost.groupby(
              network.generators.carrier).mean()[carrier]
      df['start_up_fuel'] = df['start_up_fuel'] * fuel_costs
      df['start_up_cost'] = df['start_up_cost'] + df['start_up_fuel']
      df.drop('start_up_fuel', axis=1, inplace=True)
      for tech in df.index:
          for limit in df.columns:
              network.generators.loc[network.generators.carrier == tech, 
                                     limit] = df.loc[tech, limit]
      network.generators.start_up_cost = network.generators.start_up_cost\
                                          *network.generators.p_nom
      network.generators.committable = True