code: def main() -> None:
      existing_samples: typing.Set[MatmulSize] = set()
      if os.path.isfile(_OUTPUT_FILE.value):
          existing_samples = read_timings()
      else:
          write_csv_header()
  
      run_search(existing_samples)
  
imports: import concurrent.futures
  import csv
  import itertools
  import logging
  import os
  import random
  import sys
  import time
  import typing
  from absl import app
  from absl import flags
  from matmul_lib import benchmark_matmul
  from matmul_lib import generate_tiling_configs
  from matmul_lib import MatmulSize
  from matmul_lib import MatmulTiming
  from matmul_lib import parse_int_list
  from matmul_lib import parse_layout_list
  from matmul_lib import QuantizedInputType
  import numpy
  import torch
  import tqdm
  from tqdm.contrib.logging import logging_redirect_tqdm
label_desc: Use image node_id 6 for calling a global function with example usage: main() without return types