You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: firewallrules_client_example_test.go
    path of file: ./repos/azure-sdk-for-go/sdk/resourcemanager/mysql/armmysqlflexibleservers
    
    the code of the file until where you have to start completion: //go:build go1.18
// +build go1.18

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT Licens
    
func ExampleFirewallRulesClient_BeginCreateOrUpdate() {
	cred, err := azidentity.NewDefaultAzureCredential(nil)
	if err != nil {
		log.Fatalf("failed to obtain a credential: %v", err)
	}
	ctx := context.Background()
	clientFactory, err := armmysqlflexibleservers.NewClientFactory("<subscription-id>", cred, nil)
	if err != nil {
		log.Fatalf("failed to create client: %v", err)
	}
	poller, err := clientFactory.NewFirewallRulesClient().BeginCreateOrUpdate(ctx, "TestGroup", "testserver", "rule1", armmysqlflexibleservers.FirewallRule{
		Properties: &armmysqlflexibleservers.FirewallRuleProperties{
			EndIPAddress:   to.Ptr("255.255.255.255"),
			StartIPAddress: to.Ptr("0.0.0.0"),
		},
	}, nil)
	if err != nil {
		log.Fatalf("failed to finish the request: %v", err)
	}
	res, err := poller.PollUntilDone(ctx, nil)
	if err != nil {
		log.Fatalf("failed to pull the result: %v", err)
	}
	// You could use response here. We use blank identifier for just demo purposes.
	_ = res
	// If the HTTP response code is 200 as defined in example definition, your response structure would look as follows. Please pay attention that all the values in the output are fake values for just demo purposes.
	// res.FirewallRule = armmysqlflexibleservers.FirewallRule{
	// 	Name: to.Ptr("rule1"),
	// 	Type: to.Ptr("Microsoft.DBforMySQL/flexibleServers/firewallRules"),
	// 	ID: to.Ptr("/subscriptions/ffffffff-ffff-ffff-ffff-ffffffffffff/resourceGroups/TestGroup/providers/Microsoft.DBforMySQL/flexibleServers/testserver/firewallRules/rule1"),
	// 	Properties: &armmysqlflexibleservers.FirewallRuleProperties{
	// 		EndIPAddress: to.Ptr("255.255.255.255"),
	// 		StartIPAddress: to.Ptr("0.0.0.0"),
	// 	},
	// }
}