class_docstr: **QNLI** 数据集的 **Loader** ，如果您的实验使用到了该数据，请引用
  
      https://arxiv.org/pdf/1809.05053.pdf
      
  读取数据的格式为：第一行为标题（具体内容会被忽略），之后每一行是一个 sample，由 **index** 、**问题** 、**句子** 和 **标签** 构成（以制表符分割），数据结构如下::
  
      index   question        sentence        label
      0       What came into force after the new constitution was herald?     As of that day, the new constitution heralding the Second Republic came into force.     entailment
  
  加载的 :class:`~fastNLP.core.DataSet` 将具备以下的内容： ``raw_words1`` 是 ``question`` ， ``raw_words2`` 是 ``sentence`` ， ``target`` 是 ``label`` 。
  测试集中没有 ``target`` 列。
  
  .. csv-table::
      :header: "raw_words1", "raw_words2", "target"
  
      "What came into force after the new...", "As of that day...", "entailment"
      "...","."
code: def __init__(self):
      super().__init__()
  
imports: import os
  from typing import Union, Dict
  from .csv import CSVLoader
  from .json import JsonLoader
  from .loader import Loader
  from fastNLP.io.data_bundle import DataBundle
  from ..utils import check_loader_paths
  from fastNLP.core.dataset import DataSet, Instance
  from fastNLP.core.log import logger
label_desc: Use image node_id 1 to create a new QNLILoader object from inherited base classes: JsonLoader with example: obj = QNLILoader()