code: @Override
      public PurchaseProvisionedCapacityResult purchaseProvisionedCapacity(PurchaseProvisionedCapacityRequest request) {
          request = beforeClientExecution(request);
          return executePurchaseProvisionedCapacity(request);
      }
docs: <p>
  This operation purchases a provisioned capacity unit for an AWS account.
  </p>
  
  @param purchaseProvisionedCapacityRequest
  @return Result of the PurchaseProvisionedCapacity operation returned by the service.
  @throws InvalidParameterValueException
  Returned if a parameter of the request is incorrectly specified.
  @throws MissingParameterValueException
  Returned if a required header or parameter is missing from the request.
  @throws LimitExceededException
  Returned if the request results in a vault or account limit being exceeded.
  @throws ServiceUnavailableException
  Returned if the service cannot complete the request.
  @sample AmazonGlacier.PurchaseProvisionedCapacity