code: def extract_checkpoint_number_from_metrics_filename(filename):
      match = re.search(r"ckpt-([\d]*)\.metrics", filename)
      if match:
          return int(match.group(1))
  
file_path: deepvariant/tools/print_f1.py
imports: import argparse
  import json
  import logging
  from os import listdir
  from os.path import isfile
  from os.path import join
  import re
label_desc: Use image node_id 2 for calling a global function with example usage: extract_checkpoint_number_from_metrics_filename(filename) and returns: int