class_docstr: Wizard of Wikipedia Gender gender.
class_docstr_tok: ["Wizard","of","Wikipedia","Gender","gender","."]
code: def num_episodes(self):
      return len(self.data)
  
imports: from typing import Optional
  from parlai.core.params import ParlaiParser
  from parlai.core.opt import Opt
  from parlai.core.message import Message
  from parlai.core.teachers import FixedDialogTeacher
  import parlai.tasks.md_gender.utils
  from parlai.tasks.md_gender.build import build
  from copy import deepcopy
  import json
  import os
  import random
label_desc: Use image node_id 7 for calling the WizardTeacher obj's underlying member method code with example usage: obj.num_episodes() and returns: len