code: @Override
      public PurchaseReservedInstancesOfferingResult purchaseReservedInstancesOffering(PurchaseReservedInstancesOfferingRequest request) {
          request = beforeClientExecution(request);
          return executePurchaseReservedInstancesOffering(request);
      }
docs: <p>
  Purchases a Reserved Instance for use with your account. With Reserved Instances, you pay a lower hourly rate
  compared to On-Demand instance pricing.
  </p>
  <p>
  Use <a>DescribeReservedInstancesOfferings</a> to get a list of Reserved Instance offerings that match your
  specifications. After you've purchased a Reserved Instance, you can check for your new Reserved Instance with
  <a>DescribeReservedInstances</a>.
  </p>
  <p>
  For more information, see <a
  href="https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/concepts-on-demand-reserved-instances.html">Reserved
  Instances</a> and <a href="https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ri-market-general.html">Reserved
  Instance Marketplace</a> in the <i>Amazon Elastic Compute Cloud User Guide</i>.
  </p>
  
  @param purchaseReservedInstancesOfferingRequest
  Contains the parameters for PurchaseReservedInstancesOffering.
  @return Result of the PurchaseReservedInstancesOffering operation returned by the service.
  @sample AmazonEC2.PurchaseReservedInstancesOffering
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/ec2-2016-11-15/PurchaseReservedInstancesOffering"
  target="_top">AWS API Documentation</a>