class_docstr: Use MockDict instead of regular DictionaryAgent.
class_docstr_tok: ["Use","MockDict","instead","of","regular","DictionaryAgent","."]
docstr: Null output.
docstr_tok: ["Null","output","."]
code: def eval_step(self, batch):
      """
      Null output.
      """
      return Output()
  
imports: from typing import Optional
  from parlai.core.params import ParlaiParser
  from parlai.core.opt import Opt
  from parlai.core.torch_agent import TorchAgent, Output
  import torch
  from parlai.core.agents import Agent
label_desc: Use image node_id 6 for calling the SilentTorchAgent obj's underlying member method code with example usage: obj.eval_step(batch) and returns: Output