Use str.maketrans to ensure that only hex characters are given to UUID init

Author: sevdog

Lib/uuid.py

@@ -57,7 +57,6 @@
 """
 
 import os
-import re
 import sys
 import time
 
@@ -84,6 +83,7 @@
     _MAC_DELIM = b'.'
     _MAC_OMITS_LEADING_ZEROES = True
 
+_HEX_TT = str.maketrans('', '', 'abcdefABCDEF0123456789')
 RESERVED_NCS, RFC_4122, RESERVED_MICROSOFT, RESERVED_FUTURE = [
     'reserved for NCS compatibility', 'specified in RFC 4122',
     'reserved for Microsoft compatibility', 'reserved for future definition']
@@ -216,7 +216,8 @@ def __init__(self, hex=None, bytes=None, bytes_le=None, fields=None,
         elif hex is not None:
             hex = hex.replace('urn:', '').replace('uuid:', '')
             hex = hex.strip('{}').replace('-', '')
-            if not re.fullmatch(r'[0-9A-Fa-f]{32}', hex):
+            # ensure that only 32 hex characters pass through
+            if len(hex) != 32 or hex.translate(_HEX_TT):
                 raise ValueError('badly formed hexadecimal UUID string')
             int = int_(hex, 16)
         elif bytes_le is not None: