code: def get_loss_func(loss_name):
      """
      Retrieve the loss given the loss name.
      Args (int):
          loss_name: the name of the loss to use.
      """
      if loss_name not in _LOSSES.keys():
          raise NotImplementedError(
              "Loss {} is not supported".format(loss_name)
          )
      return _LOSSES[loss_name]
  
file_path: SlowFast/slowfast/models/losses.py
imports: from functools import partial
  import torch
  import torch.nn
  from pytorchvideo.losses.soft_target_cross_entropy import SoftTargetCrossEntropyLoss
label_desc: Use image node_id 1 for calling a global function with example usage: get_loss_func(loss_name) and returns: _LOSSES