class_docstr: Base class of audio classification dataset.
class_docstr_tok: ["Base","class","of","audio","classification","dataset","."]
code: def __init__(
      self,
      base_path: str,
      data_file: str,
      file_type: str = "npz",
      mode: str = "train",
      feat_type: str = "mel",
      feat_cfg: dict = None,
  ):
      super(AudioClassificationDataset, self).__init__(
          base_path=base_path, mode=mode, data_file=data_file
      )
  
      self.file_type = file_type
      self.feat_type = feat_type
      self.feat_cfg = feat_cfg
  
      self.examples = self._read_file(self.data_file)
      self.records = self._convert_examples_to_records(self.examples)
  
imports: import csv
  import io
  import os
  from typing import Dict, List, Optional, Tuple, Union
  import numpy
  import paddle
  from paddlehub.utils.utils import extract_melspectrogram
label_desc: Use image node_id 1 to create a new AudioClassificationDataset object from inherited base classes: BaseAudioDataset, paddle.io with example: obj = AudioClassificationDataset(base_path, data_file, file_type, mode, feat_type, feat_cfg)