code: @Override
      public DescribeUsersResult describeUsers(DescribeUsersRequest request) {
          request = beforeClientExecution(request);
          return executeDescribeUsers(request);
      }
docs: <p>
  Retrieves a list that describes one or more specified users in the user pool.
  </p>
  
  @param describeUsersRequest
  @return Result of the DescribeUsers operation returned by the service.
  @throws ResourceNotFoundException
  The specified resource was not found.
  @throws InvalidParameterCombinationException
  Indicates an incorrect combination of parameters, or a missing parameter.
  @sample AmazonAppStream.DescribeUsers
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/appstream-2016-12-01/DescribeUsers" target="_top">AWS API
  Documentation</a>