code: def run_genotyper(bam_file, ref_file, dbsnp_file, config_file):
      
      cl = ["gatk_genotyper.py", config_file, ref_file, bam_file]
      if dbsnp_file:
          cl.append(dbsnp_file)
      subprocess.check_call(cl)
docs: Perform SNP genotyping and analysis using GATK.