docs: def parse_passage(obj: dict) -> BioCPassage:
      """Deserialize a dict obj to a BioCPassage object"""
      passage = BioCPassage()
      passage.offset = obj['offset']
      passage.infons = obj['infons']
      if 'text' in obj:
          passage.text = obj['text']
      for sentence in obj['sentences']:
          passage.add_sentence(parse_sentence(sentence))
      for annotation in obj['annotations']:
          passage.add_annotation(parse_annotation(annotation))
      for relation in obj['relations']:
          passage.add_relation(parse_relation(relation))
      return passage