code: func (gce *Cloud) CreateGlobalForwardingRule(targetProxyLink, ip, name, portRange string) (*compute.ForwardingRule, error) {
  	rule := &compute.ForwardingRule{
  		Name:       name,
  		IPAddress:  ip,
  		Target:     targetProxyLink,
  		PortRange:  portRange,
  		IPProtocol: "TCP",
  	}
  	op, err := gce.service.GlobalForwardingRules.Insert(gce.projectID, rule).Do()
  	if err != nil {
  		return nil, err
  	}
  	if err = gce.waitForGlobalOp(op); err != nil {
  		return nil, err
  	}
  	return gce.GetGlobalForwardingRule(name)
  }
docs: // GlobalForwardingRule management
  // CreateGlobalForwardingRule creates and returns a GlobalForwardingRule that points to the given TargetHttp(s)Proxy.
  // targetProxyLink is the SelfLink of a TargetHttp(s)Proxy.