code: func (m *kubeGenericRuntimeManager) determinePodSandboxIP(podNamespace, podName string, podSandbox *runtimeapi.PodSandboxStatus) string {
  	if podSandbox.Network == nil {
  		klog.Warningf("Pod Sandbox status doesn't have network information, cannot report IP")
  		return ""
  	}
  	ip := podSandbox.Network.Ip
  	if len(ip) != 0 && net.ParseIP(ip) == nil {
  		// ip could be an empty string if runtime is not responsible for the
  		// IP (e.g., host networking).
  		klog.Warningf("Pod Sandbox reported an unparseable IP %v", ip)
  		return ""
  	}
  	return ip
  }
docs: // determinePodSandboxIP determines the IP address of the given pod sandbox.