code: def lstm(*args, **kwargs):
      raise NotImplementedError
  
file_path: keras/keras/backend/torch/rnn.py
imports: import torch
  import tree
  from keras.backend.torch.core import convert_to_tensor
  from keras.utils.nest import pack_sequence_as
label_desc: Use image node_id 3 for calling a global function with example usage: lstm() without return types