code: def trace(a: Union[torch.Tensor, ComplexTensor]):
      # NOTE (wangyou): until PyTorch 1.9.0, torch.trace does not
      # support bacth processing. Use FC.trace() as fallback.
      return FC.trace(a)
  
file_path: espnet/espnet2/enh/layers/complex_utils.py
imports: from typing import Sequence, Tuple, Union
  import torch
  from torch_complex import functional
  from torch_complex.tensor import ComplexTensor
label_desc: Use image node_id 12 for calling a global function with example usage: trace(a) and returns: FC