class_docstr: Simple LSTModel for testing.
  
  Args:
      output_dim (int): Dimension of the network output.
      hidden_dim (int): Hidden dimension for LSTM cell.
      name (str): Model name, also the variable scope.
      args (list): Unused positionl arguments.
      kwargs (dict): Unused keyword arguments.
docstr: Network output spec.
  
  Return:
      list[str]: List of key(str) for the network outputs.
docstr_tok: ["Network","output","spec",".","Return",":","list","[","str","]",":","List","of","key","(","str",")","for","the","network","outputs","."]
code: def network_output_spec(self):
      """Network output spec.
  
      Return:
          list[str]: List of key(str) for the network outputs.
  
      """
      return [
          "all_output",
          "step_output",
          "step_hidden",
          "step_cell",
          "init_hidden",
          "init_cell",
      ]
  
imports: import tensorflow
  from garage.tf.models import Model
label_desc: Use image node_id 3 for calling the SimpleLSTMModel obj's underlying member method code with example usage: obj.network_output_spec() and returns: list