docs: def _on_power_state(self, header, payload, rest, addr):
          """
          Records the power (on/off) state of bulbs, and forwards to a high-level
          callback with human-friendlier arguments.
          """
          with self.lock:
              self.power_state[header.mac] = payload
              if len(self.power_state) >= self.num_bulbs:
                  self.power_state_event.set()
  
          self.callbacks.put(EVENT_POWER_STATE, self.get_bulb(header.mac),
                             is_on=bool(payload['is_on']))