code: @Override
      public DescribeAttachmentResult describeAttachment(DescribeAttachmentRequest request) {
          request = beforeClientExecution(request);
          return executeDescribeAttachment(request);
      }
docs: <p>
  Returns the attachment that has the specified ID. Attachment IDs are generated by the case management system when
  you add an attachment to a case or case communication. Attachment IDs are returned in the
  <a>AttachmentDetails</a> objects that are returned by the <a>DescribeCommunications</a> operation.
  </p>
  
  @param describeAttachmentRequest
  @return Result of the DescribeAttachment operation returned by the service.
  @throws InternalServerErrorException
  An internal server error occurred.
  @throws DescribeAttachmentLimitExceededException
  The limit for the number of <a>DescribeAttachment</a> requests in a short period of time has been
  exceeded.
  @throws AttachmentIdNotFoundException
  An attachment with the specified ID could not be found.
  @sample AWSSupport.DescribeAttachment
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/support-2013-04-15/DescribeAttachment" target="_top">AWS API
  Documentation</a>