text: Title: using pytorch training reference script with pytorch-metric-learning
  Body: Hi @KevinMusgrave !
  
  I have recently been using the reference scripts pytorch provides to train my models (which is wonderful btw) BUT, I would love to use pytorch-metric-learning with this reference script.
  
  The training script and blog re this is here:
  https://github.com/pytorch/vision/tree/main/references/classification
  https://pytorch.org/blog/how-to-train-state-of-the-art-models-using-torchvision-latest-primitives/
  
  I am particularly interested in classification:
  https://github.com/pytorch/vision/blob/main/references/classification/train.py
  
  However, the issue ofc is that they all use CE loss which requires the logits - but I am not sure how to use say ArcFace Loss with this training reference script. Essentially, I would need the logits to make this work, but atm, all my arcface loss models work with an embedder output and distance metrics.
  
  I was wondering if you could provide some guidance/advise on how to proceed to include metric learning in the reference training script.
  
  Thank you!
  
  