class_docstr: Document Encoder for DPR.
class_docstr_tok: ["Document","Encoder","for","DPR","."]
code: def __init__(self, *args, **kwargs):
      kwargs["encoder_type"] = "document"
      super().__init__(*args, **kwargs)
  
imports: from parlai.agents.transformer.transformer import TransformerRankerAgent
  from parlai.agents.transformer.modules import TransformerMemNetModel, TransformerEncoder
  from parlai.agents.hugging_face.dict import HuggingFaceDictionaryAgent
  from parlai.agents.rag.args import DPR_ZOO_MODEL
  from parlai.agents.rag.conversion_utils import BertConversionUtils
  from parlai.core.build_data import modelzoo_path
  from parlai.core.dict import DictionaryAgent
  from parlai.core.loader import register_agent
  from parlai.core.opt import Opt
  from parlai.core.torch_ranker_agent import TorchRankerAgent
  from parlai.utils.io import PathManager
  import parlai.utils.logging
  import os
  import torch
  import torch.cuda
  import torch.nn
  from transformers import BertConfig
  from typing import Dict, Optional
label_desc: Use image node_id 1 to create a new DprDocumentEncoder object from inherited base classes: DprEncoder with example: obj = DprDocumentEncoder()