code: def is_complex(c):
      return isinstance(c, ComplexTensor) or is_torch_complex_tensor(c)
  
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 3 for calling a global function with example usage: is_complex(c) and returns: unknown