class_docstr: GramVaaniCSV representing a GramVaani dataset.
  Args:
    csv_filename (str): Path to the GramVaani csv
  Attributes:
      data (:class:`pandas.DataFrame`): `pandas.DataFrame` Containing the GramVaani csv data
code: def _parse_csv(self, csv_filename):
      _logger.info(
          "Parsing csv file...%s", os.path.abspath(csv_filename)
      )
      data = pd.read_csv(
          os.path.abspath(csv_filename),
          names=[
              "piece_id",
              "audio_url",
              "transcript_labelled",
              "transcript",
              "labels",
              "content_filename",
              "audio_length",
              "user_id",
          ],
          usecols=["audio_url", "transcript", "audio_length"],
          skiprows=[0],
          engine="python",
          encoding="utf-8",
          quotechar='"',
          quoting=csv.QUOTE_ALL,
      )
      data.dropna(inplace=True)
      _logger.info("Parsed %d lines csv file." % len(data))
      return data
  
imports: import csv
  import logging
  import math
  import os
  import subprocess
  import urllib
  from pathlib import Path
  import pandas
  from sox import Transformer
  import swifter
  from deepspeech_training.util.importers import get_importers_parser, get_validate_label
label_desc: Use image node_id 2 for calling the GramVaaniCSV obj's underlying member method code with example usage: obj._parse_csv(csv_filename) and returns: data