code: def _mix_labels(
      labels: torch.Tensor,
      num_classes: int,
      lam: float = 1.0,
      label_smoothing: float = 0.0,
      one_hot: bool = False,
  ):
      """
      This function converts class indices to one-hot vectors and mix labels, given the
      number of classes.
  
      Args:
          labels (torch.Tensor): Class labels.
          num_classes (int): Total number of classes.
          lam (float): lamba value for mixing labels.
          label_smoothing (float): Label smoothing value.
      """
      if one_hot:
          labels1 = labels
          labels2 = labels.flip(0)
      else:
          labels1 = convert_to_one_hot(
              labels, num_classes, label_smoothing
          )
          labels2 = convert_to_one_hot(
              labels.flip(0), num_classes, label_smoothing
          )
      return labels1 * lam + labels2 * (1.0 - lam)
  
file_path: pytorchvideo/pytorchvideo/transforms/mix.py
imports: from typing import Any, Dict, Tuple
  import torch
  from pytorchvideo.transforms.functional import convert_to_one_hot
label_desc: Use image node_id 1 for calling a global function with example usage: _mix_labels(labels, num_classes, lam, label_smoothing, one_hot) and returns: unknown