class_docstr: The base teacher class for Natural Questions dataset challenge.
  
  This class implements the core functionalities for other teachers. The other four
  variations of teachers are made by setting two object attributes (use_html,
  use_long_answer) to either True or False.
class_docstr_tok: ["The","base","teacher","class","for","Natural","Questions","dataset","challenge",".","This","class","implements","the","core","functionalities","for","other","teachers",".","The","other","four","variations","of","teachers","are","made","by","setting","two","object","attributes","(","use_html",",","use_long_answer",")","to","either","True","or","False","."]
code: def get_num_samples(self, opt) -> Tuple[int, int]:
      if self.dtype == "train":
          self.n_samples = (307373, 307373)
      else:
          self.n_samples = (7830, 7830)
      return self.n_samples
  
imports: import copy
  import os
  import json
  import jsonlines
  from typing import List, Optional, Tuple
  from parlai.core.teachers import ChunkTeacher, DialogTeacher
  from .build import build, DATASET_NAME_LOCAL, build_sample
  from .build_open import build
  from .utils.text_utils import simplify_nq_example
  from parlai.core.opt import Opt
  from parlai.core.message import Message
  from parlai.core.metrics import ExactMatchMetric, normalize_answer, AverageMetric
  from parlai.core.params import ParlaiParser
  from parlai.utils.data import DatatypeHelper
  from parlai.utils.io import PathManager
  import parlai.utils.logging
label_desc: Use image node_id 6 for calling the NaturalQuestionsTeacher obj's underlying member method code with example usage: obj.get_num_samples(opt) and returns: self