code: def _calculate_data_set_sizes(self):
      total_size = len(self.valid)
      dev_size = math.floor(total_size * DEV_PERCENTAGE)
      train_size = math.floor(total_size * TRAIN_PERCENTAGE)
      test_size = total_size - (train_size + dev_size)
      return (train_size, dev_size, test_size)
  
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 9 for calling the GramVaaniDataSets obj's underlying member method code with example usage: obj._calculate_data_set_sizes() and returns: train_size,  dev_size,  test_size