class_docstr: This is a helper for replicating the history object
  behavior of Keras to make Talos Scan() API consistent between
  the two backends.
code: def append_val_metric(self, _loss):
      self.append_history(_loss, "val_metric")
  
file_path: talos/talos/utils/torch_history.py
label_desc: Use image node_id 7 for calling the TorchHistory obj's underlying member method code with example usage: obj.append_val_metric(_loss) without return types