code: def calculate_power_output(self, wind_speed_hub, density_hub):
          r
          if self.power_output_model == 'power_curve':
              if self.power_plant.power_curve is None:
                  raise TypeError("Power curve values of " +
                                  self.power_plant.name +
                                  " are missing.")
              logging.debug('Calculating power output using power curve.')
              return (power_output.power_curve(
                          wind_speed_hub,
                          self.power_plant.power_curve['wind_speed'],
                          self.power_plant.power_curve['value'],
                          density_hub, self.density_correction))
          elif self.power_output_model == 'power_coefficient_curve':
              if self.power_plant.power_coefficient_curve is None:
                  raise TypeError("Power coefficient curve values of " +
                                  self.power_plant.name +
                                  " are missing.")
              logging.debug('Calculating power output using power coefficient '
                            'curve.')
              return (power_output.power_coefficient_curve(
                          wind_speed_hub,
                          self.power_plant.power_coefficient_curve[
                              'wind_speed'],
                          self.power_plant.power_coefficient_curve[
                              'value'],
                          self.power_plant.rotor_diameter, density_hub))
          else:
              raise ValueError("'{0}' is an invalid value. ".format(
                               self.power_output_model) +
                               "`power_output_model` must be " +
                               "'power_curve' or 'power_coefficient_curve'.")
docs: r"""
          Calculates the power output of the wind power plant.
  
          The method specified by the parameter `power_output_model` is used.
  
          Parameters
          ----------
          wind_speed_hub : pandas.Series or numpy.array
              Wind speed at hub height in m/s.
          density_hub : pandas.Series or numpy.array
              Density of air at hub height in kg/m³.
  
          Returns
          -------
          pandas.Series
              Electrical power output of the wind turbine in W.