Use aware timestamps in inventory

utils.py

@@ -7,6 +7,7 @@ import logging
 from functools import wraps
 from contextlib import suppress
 from collections import OrderedDict
+from datetime import datetime, timezone
 from typing import Union, List, MutableSet, Iterable, Iterator, Generic, TypeVar
 
 from constants import JsonType
@@ -18,6 +19,10 @@ logger = logging.getLogger("TwitchDrops")
 NONCE_CHARS = string.ascii_letters + string.digits
 
 
+def timestamp(string: str) -> datetime:
+    return datetime.strptime(string, "%Y-%m-%dT%H:%M:%SZ").replace(tzinfo=timezone.utc)
+
+
 def create_nonce(length: int = 30) -> str:
     return ''.join(random.choices(NONCE_CHARS, k=length))