code: @Override
      public DescribeChapCredentialsResult describeChapCredentials(DescribeChapCredentialsRequest request) {
          request = beforeClientExecution(request);
          return executeDescribeChapCredentials(request);
      }
docs: <p>
  Returns an array of Challenge-Handshake Authentication Protocol (CHAP) credentials information for a specified
  iSCSI target, one for each target-initiator pair.
  </p>
  
  @param describeChapCredentialsRequest
  A JSON object containing the Amazon Resource Name (ARN) of the iSCSI volume target.
  @return Result of the DescribeChapCredentials operation returned by the service.
  @throws InvalidGatewayRequestException
  An exception occurred because an invalid gateway request was issued to the service. For more information,
  see the error and message fields.
  @throws InternalServerErrorException
  An internal server error has occurred during the request. For more information, see the error and message
  fields.
  @sample AWSStorageGateway.DescribeChapCredentials
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/storagegateway-2013-06-30/DescribeChapCredentials"
  target="_top">AWS API Documentation</a>