so this D solves these problems and it's very clever and there are algorithms to compute these these minimum matchings and they use the Hungarian algorithm which will give you exactly such a matching again this is possible because you have n things on each side and the N is in effect here is a the maximum of objects that you can detect at once I guess if there is less you can simply pad right here and then the model of course is encouraged to come up with the equal number of no class predictions because if it outputs a prediction when it