code: def combine_files(output_filename, *input_filenames):
      """
      Combine multiple NER json files into one NER file
      """
      doc = []
  
      for filename in input_filenames:
          with open(filename) as fin:
              new_doc = json.load(fin)
              doc.extend(new_doc)
  
      with open(output_filename, "w") as fout:
          json.dump(doc, fout, indent=2)
  
imports: from collections import defaultdict
  import json
  import os
  import random
  from stanza.models.common.doc import Document
  import stanza.utils.datasets.ner.prepare_ner_file
label_desc: Use image node_id 15 for calling a global function with example usage: combine_files(output_filename) without return types