class_docstr: Augmented Data.
  
  To mimic the way ParlAI generally handles dialogue datasets, the data associated
  with this teacher is presented in a format such that a single "episode" is split
  across multiple entries.
  
  I.e., suppose we have the following dialogue between speakers 1 and 2:
  utterances: [A, B, C, D, E],
  label: F
  
  The data in this file is split such that we have the following episodes:
  
  ep1:
      utterances: [A],
      label: B
  ep2:
      utterances [A, B, C]
      label: D
  ep3:
      utterances: [A, B, C, D, E],
      label: F
code: def get_suffix(self):
      if self.split != "train":
          return ""
      return "_augmented"
  
imports: from parlai.core.teachers import FixedDialogTeacher
  from parlai.utils.io import PathManager
  from .build import build
  import json
  import os
  import random
label_desc: Use image node_id 1 for calling the DSTC7TeacherAugmented obj's underlying member method code with example usage: obj.get_suffix() and returns: str, str