code: def get_true_capacity(self):
          
  
          c = self.capacity
          if c is not None:
              return c
          else:
              if self.rooms.count() == 0 and self.activity.default_capacity:
                  # use activity-level override
                  return self.activity.default_capacity
  
              rooms = self.get_true_rooms()
              return EighthRoom.total_capacity_of_rooms(rooms)
docs: Get the capacity for the scheduled activity, taking into account activity defaults and
          overrides.