Hello all.
I am importing the model as  frcnn = fasterrcnn_resnet50_fpn(pretrained=False,                                 num_classes=6,                                 pretrained_backbone=True,                                 progress=True)
In the docs it is written that I have to pass a list of images and targets which would return the cls_loss and regression_loss,
I am sorry this might be a silly question, but we have to propagate the loss backward, or is the loss.backward() or optim.step() taken care of internally?
TIA