code: def _set_reject(line):
      
      if line.startswith("#"):
          return line
      parts = line.split("\t")
      if parts[6] == "PASS":
          parts[6] = "REJECT"
      else:
          parts[6] += ";REJECT"
      return "\t".join(parts)
docs: Set REJECT in VCF line, or add it if there is something else.