code: func newCheckKey(vip, bip seesaw.IP, port uint16, proto seesaw.IPProto, h *config.Healthcheck) checkKey {
  	return checkKey{
  		vserverIP:       vip,
  		backendIP:       bip,
  		servicePort:     port,
  		serviceProtocol: proto,
  		healthcheckMode: h.Mode,
  		healthcheckType: h.Type,
  		healthcheckPort: h.Port,
  		name:            h.Name,
  	}
  }
docs: // newCheckKey returns an initialised checkKey.