code: def __init__(self, opt, dictionary, retriever_shared=None):
      super().__init__(opt, dictionary, retriever_shared)
      if opt.get("fid_ddp_compatible", True):
          for param in self.long_term_memory.query_encoder.parameters():
              param.requires_grad = False
          for (
              param
          ) in self.long_term_memory.memory_encoder.parameters():
              param.requires_grad = False
          for param in self.retriever.parameters():
              param.requires_grad = False
  
imports: from typing import Optional, Union
  from parlai.core.message import Message
  from parlai.core.opt import Opt
  from parlai.core.params import ParlaiParser
  from projects.blenderbot2.agents.sub_modules import KnowledgeAccessMethod
  from projects.blenderbot2.agents.modules import T5BlenderBot2RagModel, BlenderBot2RagModel, T5BlenderBot2FidModel, BlenderBot2FidModel, BlenderBot2FidModelMixin
  import torch
  from projects.blenderbot2.agents.blenderbot2 import BlenderBot2RagAgent
  from .long_rag import LongRagAgent, LongRagModel, LongFidAgent, LongFidModel
label_desc: Use image node_id 2 to create a new MemoryLongFidModel object from inherited base classes: BlenderBot2FidModelMixin, MemoryLongRagModel, LongFidModel with example: obj = MemoryLongFidModel(opt, dictionary, retriever_shared)