class_docstr: Class to manage save and restore for the model and optimizer.
docstr: Restores model and optimizer from given directory.
  
  Returns:
     Last training step for the model restored.
docstr_tok: ["Restores","model","and","optimizer","from","given","directory",".","Returns",":","Last","training","step","for","the","model","restored","."]
code: def restore(self, model_dir, map_to_cpu=False):
      """Restores model and optimizer from given directory.
  
      Returns:
         Last training step for the model restored.
      """
      last_step = load_checkpoint(
          self._model, self._optimizer, model_dir, map_to_cpu
      )
      return last_step
  
imports: import os
label_desc: Use image node_id 2 for calling the Saver obj's underlying member method code with example usage: obj.restore(model_dir, map_to_cpu) and returns: last_step