code: @Override
      public DescribeTransitGatewayVpcAttachmentsResult describeTransitGatewayVpcAttachments(DescribeTransitGatewayVpcAttachmentsRequest request) {
          request = beforeClientExecution(request);
          return executeDescribeTransitGatewayVpcAttachments(request);
      }
docs: <p>
  Describes one or more VPC attachments. By default, all VPC attachments are described. Alternatively, you can
  filter the results.
  </p>
  
  @param describeTransitGatewayVpcAttachmentsRequest
  @return Result of the DescribeTransitGatewayVpcAttachments operation returned by the service.
  @sample AmazonEC2.DescribeTransitGatewayVpcAttachments
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/ec2-2016-11-15/DescribeTransitGatewayVpcAttachments"
  target="_top">AWS API Documentation</a>