class_docstr: Convert some results to :obj:`torch.Tensor` by given keys.
  
  Args:
      keys (Sequence[str]): Keys that need to be converted to Tensor.
docstr: Call function to convert data in results to :obj:`torch.Tensor`.
  
  Args:
      results (dict): Result dict contains the data to convert.
  
  Returns:
      dict: The result dict contains the data converted
          to :obj:`torch.Tensor`.
code: def __call__(self, results):
      """Call function to convert data in results to :obj:`torch.Tensor`.
  
      Args:
          results (dict): Result dict contains the data to convert.
  
      Returns:
          dict: The result dict contains the data converted
              to :obj:`torch.Tensor`.
      """
      for key in self.keys:
          results[key] = to_tensor(results[key])
      return results
  
imports: from typing import Optional, Sequence
  import numpy
  from mmcv.transforms import to_tensor
  from mmcv.transforms.base import BaseTransform
  from mmengine.structures import InstanceData, PixelData
  from mmdet.registry import TRANSFORMS
  from mmdet.structures import DetDataSample, ReIDDataSample, TrackDataSample
  from mmdet.structures.bbox import BaseBoxes
label_desc: Use image node_id 2 for calling the ToTensor obj's underlying member method code with example usage: obj.__call__(results) and returns: results