| import re | |
| CAS_RX = re.compile(r"^\d{2,7}-\d{2}-\d$") | |
| DTXSID_RX = re.compile(r"^DTXSID\d{7,}$") | |
| def is_cas(s: str) -> bool: | |
| return bool(CAS_RX.match((s or "").strip())) | |
| def normalize_cas(s: str) -> str: | |
| return (s or "").strip() | |
| def is_dtxsid(s: str) -> bool: | |
| return bool(DTXSID_RX.match((s or "").strip())) |