code: def convert_spot_asoc(spot_asoc_instance, structure_maker):
      """将一个 Spot-Asoc 实例转换成目标字符串
  
      Args:
          spot_asoc_instance ([type]): [description]
          structure_maker ([type]): [description]
  
      Returns:
          [type]: [description]
      """
      spot_instance_str_rep_list = list()
      for spot in spot_asoc_instance:
          spot_str_rep = [
              spot["label"],
              structure_maker.target_span_start,
              spot["span"],
          ]
          for asoc_label, asoc_span in spot.get("asoc", list()):
              asoc_str_rep = [
                  structure_maker.span_start,
                  asoc_label,
                  structure_maker.target_span_start,
                  asoc_span,
                  structure_maker.span_end,
              ]
              spot_str_rep += [" ".join(asoc_str_rep)]
          spot_instance_str_rep_list += [
              " ".join(
                  [
                      structure_maker.record_start,
                      " ".join(spot_str_rep),
                      structure_maker.record_end,
                  ]
              )
          ]
      target_text = " ".join(
          [
              structure_maker.sent_start,
              " ".join(spot_instance_str_rep_list),
              structure_maker.sent_end,
          ]
      )
      return target_text
  
label_desc: Use image node_id 1 for calling a global function with example usage: convert_spot_asoc(spot_asoc_instance, structure_maker) and returns: target_text