code: def filter(self, label):
      if self.normalize:
          label = (
              unicodedata.normalize("NFKD", label.strip())
              .encode("ascii", "ignore")
              .decode("ascii", "ignore")
          )
      label = self.validate_fun(label)
      if self.alphabet and label and not self.alphabet.CanEncode(label):
          label = None
      return label
  
file_path: DeepSpeech/bin/import_cv2.py
imports: import csv
  import os
  import subprocess
  import unicodedata
  from multiprocessing import Pool
  import progressbar
  import sox
  from deepspeech_training.util.downloader import SIMPLE_BAR
  from deepspeech_training.util.importers import get_counter, get_imported_samples, get_importers_parser, get_validate_label, print_import_report
  from ds_ctcdecoder import Alphabet
label_desc: Use image node_id 2 for calling the LabelFilter obj's underlying member method code with example usage: obj.filter(label) and returns: label