code: func (state *DockerTaskEngineState) ENIByMac(mac string) (*apieni.ENIAttachment, bool) {
  	state.lock.RLock()
  	defer state.lock.RUnlock()
  
  	eni, ok := state.eniAttachments[mac]
  	return eni, ok
  }
docs: // ENIByMac returns the eni object that match the give mac address