What is extreme multi-label classification(XMLC)

1

I tried solving a problem in recommendation systems using PyTorch, and i came this in an article, so ill like to how to use it and apply it to solve problems in recommendation systems?
Thanks

2

Based on this post by PapersWithCode it seems that Amazon provided a library based on PyTorch called PECOS for this use case, so you might want to take a look at their implementation and how the large space of labels is taken care of.