code: def string_label_to_class_id(
      string_label, label_classes, default=-1, **unused_kwargs
  ):
      """Returns index of string_label in label_classes or default if not found."""
      if string_label in label_classes:
          return label_classes.index(string_label)
      else:
          return default
  
file_path: text-to-text-transfer-transformer/t5/data/postprocessors.py
imports: import tensorflow.compat.v2
label_desc: Use image node_id 3 for calling a global function with example usage: string_label_to_class_id(string_label, label_classes, default) and returns: label_classes, default