code: func (poc PortOpenCheck) Check() (warnings, errorList []error) {
  	klog.V(1).Infof("validating availability of port %d", poc.port)
  	errorList = []error{}
  	ln, err := net.Listen("tcp", fmt.Sprintf(":%d", poc.port))
  	if err != nil {
  		errorList = append(errorList, errors.Errorf("Port %d is in use", poc.port))
  	}
  	if ln != nil {
  		ln.Close()
  	}
  
  	return nil, errorList
  }
docs: // Check validates if the particular port is available.