code: def reader(file_path, vocab):
      with PathManager.open(file_path, "r") as reader:
          for line in reader:
              yield " ".join(
                  vocab.get(s.strip(), SpecialTokens.UNK)
                  # ATIS every row starts/ends with BOS/EOS: remove them
                  for s in line.split()[1:-1]
              )
  
file_path: pytext/demo/my_tagging/source.py
imports: import os
  from random import Random
  from typing import Dict, List, Type
  from pytext.common.constants import SpecialTokens
  from pytext.data.sources.data_source import RootDataSource
  from pytext.utils.file_io import PathManager
label_desc: Use image node_id 2 for calling a global function with example usage: reader(file_path, vocab) without return types