code: def create_gemini_db(gemini_vcf, data, gemini_db=None, ped_file=None):
      
      if not gemini_db:
          gemini_db = "%s.db" % utils.splitext_plus(gemini_vcf)[0]
      if not vcfutils.vcf_has_variants(gemini_vcf):
          return None
      if not utils.file_exists(gemini_db):
          with file_transaction(data, gemini_db) as tx_gemini_db:
              vcf2db = config_utils.get_program("vcf2db.py", data)
              if "vcf2db_expand" in dd.get_tools_on(data):
                  vcf2db_args = ["--expand", "gt_types", "--expand", "gt_ref_depths", "--expand", "gt_alt_depths"]
              else:
                  vcf2db_args = []
              cmd = [vcf2db, gemini_vcf, ped_file, tx_gemini_db] + vcf2db_args
              do.run(cmd, "GEMINI: create database with vcf2db")
      return gemini_db
docs: Generalized vcfanno/vcf2db workflow for loading variants into a GEMINI database.