You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: euclidean.m
    path of file: ./repos/3DMMasSTN/dagnn
    
    the code of the file until where you have to start completion: % Wrapper for vl_nneuclideanloss block

classdef euclidean < dagnn.Loss    
    methods
        function outputs = forward(obj, inputs, ~)
            
            label=inputs{2}(:,1:2,:,:);
            vis=inputs{2}(:,
    
function [derInputs, derParams] = backward(~, inputs, ~, derOutputs)
            
            label=inputs{2}(:,1:2,:,:);
            vis=inputs{2}(:,3,:,:);
            
            useGPU = isa(inputs{1}, 'gpuArray');
            if useGPU
                derInputs{1} = gpuArray(vl_nneuclideanloss(gather(inputs{1}), gather(label), gather(vis), gather(derOutputs{1})));
            else
                derInputs{1} = vl_nneuclideanloss(inputs{1}, label, vis, derOutputs{1});
            end