as i understand, doing this:
for (auto item:loss){
          item.backward();
      }

or
loss.sum().backward()

should have more or less the same results. But neither is what i have in mind.
For example, if the errors are [1,0], by doing loss.sum().backward(), i am encouraging the whole system by 1, which is not my intention. What I want to do is to backpropagate 1 from the first output and 0 from the second output