class_docstr: COCO default teacher that expects open-ended descriptions of images.
class_docstr_tok: ["COCO","default","teacher","that","expects","open-ended","descriptions","of","images","."]
code: def add_cmdline_args(
      cls, parser: ParlaiParser, partial_opt: Optional[Opt] = None
  ) -> ParlaiParser:
      super().add_cmdline_args(parser, partial_opt)
      agent = parser.add_argument_group("COCO Caption arguments")
      agent.add_argument(
          "--use_intro",
          type="bool",
          default=False,
          help="Include an intro question with each image \
                                  for readability (e.g. for coco_caption, \
                                  Describe the above picture in a sentence.)",
      )
      agent.add_argument(
          "--num_cands",
          type=int,
          default=150,
          help="Number of candidates to use during \
                                  evaluation, setting to -1 uses all.",
      )
      agent.add_argument(
          "--include_rest_val",
          type="bool",
          default=False,
          help="Include unused validation images in training",
      )
      agent.add_argument(
          "--test-split",
          type=int,
          default=-1,
          choices=[-1, 0, 1, 2, 3, 4],
          help="Which 1k image split of dataset to use for candidates"
          "if -1, use all 5k test images",
      )
      return parser
  
imports: from typing import Optional
  from parlai.core.params import ParlaiParser
  from parlai.core.opt import Opt
  from parlai.core.teachers import FixedDialogTeacher
  from parlai.core.image_featurizers import ImageLoader
  from parlai.utils.io import PathManager
  from .build_2014 import build
  from .build_2014 import buildImage
  from .build_2017 import build
  from .build_2017 import buildImage
  import os
  import json
  import random
label_desc: Use image node_id 2 for calling the DefaultTeacher obj's underlying member method code with example usage: obj.add_cmdline_args(cls, parser, partial_opt) and returns: parser