code: def main(argv):
      with errors.clean_commandline_error_exit():
          if len(argv) > 1:
              errors.log_and_raise(
                  "Command line parsing failure: vcf_stats_report does not accept "
                  "positional arguments but some are present on the command line: "
                  '"{}".'.format(str(argv[1:])),
                  errors.CommandLineError,
              )
  
      with vcf.VcfReader(_INPUT_VCF.value) as reader:
          sample_names = reader.header.sample_names
          if len(sample_names) != 1:
              raise ValueError(
                  "There must be exactly one sample in VCF: {}".format(
                      _INPUT_VCF.value
                  )
              )
          sample_name = sample_names[0]
  
          # Check for missing GT in VCF to avoid a confusing error downstream.
          vcf_columns = [col.id for col in reader.header.formats]
          if "GT" not in vcf_columns:
              errors.log_and_raise("ERROR: No GT sub-column in VCF.")
  
          if _NUM_RECORDS.value < 0:
              variants = reader.iterate()
          else:
              variants = itertools.islice(
                  reader.iterate(), FLAGS.num_records
              )
  
          vcf_stats.create_vcf_report(
              variants,
              output_basename=_OUTFILE_BASE.value,
              title=_TITLE.value or sample_name,
              vcf_reader=reader,
          )
  
imports: import itertools
  from absl import flags
  import tensorflow
  from deepvariant import vcf_stats
  from third_party.nucleus.io import vcf
  from third_party.nucleus.util import errors
label_desc: Use image node_id 1 for calling a global function with example usage: main(argv) without return types