Sets a unique, case-sensitive identifier you provide 
            to ensure idempotency of your listings. 
            
 Declaration Syntax
 Declaration Syntax| C# | 
[ObsoleteAttribute("The With methods are obsolete and will be removed in version 2 of the AWS SDK for .NET. See http://aws.amazon.com/sdkfornet/#version2 for more information.")] public CreateReservedInstancesListingRequest WithClientToken( string clientToken )
 Parameters
 Parameters- clientToken (String)
- Identifier
 Return Value
 Return Valuethis instance
 Remarks
 Remarks
            This helps avoid duplicate listings. For more information, see 
            'Ensuring Idempotency' in the Amazon Elastic Compute Cloud User Guide.