class_docstr: Builds a string iteratively and keeps track of offsets.
  Chunks of plain text and semantic annotations need to added in order
code: def get_annotations(self):
      return self.annotations
  
file_path: datasets-server/services/worker/vendors/trec-car-tools/python3/annotated_content.py
imports: from trec_car.read_data import *
label_desc: Use image node_id 4 for calling the AnnotatedContentBuilder obj's underlying member method code with example usage: obj.get_annotations() and returns: self