code: @Override
      public DescribeSubscriptionResult describeSubscription(DescribeSubscriptionRequest request) {
          request = beforeClientExecution(request);
          return executeDescribeSubscription(request);
      }
docs: <p>
  Provides details about the AWS Shield Advanced subscription for an account.
  </p>
  
  @param describeSubscriptionRequest
  @return Result of the DescribeSubscription operation returned by the service.
  @throws InternalErrorException
  Exception that indicates that a problem occurred with the service infrastructure. You can retry the
  request.
  @throws ResourceNotFoundException
  Exception indicating the specified resource does not exist.
  @sample AWSShield.DescribeSubscription
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/shield-2016-06-02/DescribeSubscription" target="_top">AWS
  API Documentation</a>