[sso-admin] Add cache decorator for python 3.7

dd-sso/admin/src/admin/lib/keys.py

@@ -37,7 +37,7 @@ import stat
 from copy import deepcopy
 from datetime import datetime, timedelta
 from pathlib import Path
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Callable, Dict, List, Optional, Union
 
 import requests
 from attr import field, frozen
@@ -52,10 +52,15 @@ from jose.backends.rsa_backend import RSAKey
 from jose.constants import ALGORITHMS
 
 try:
-    # Python 3.8
-    from functools import cached_property as cache
-except ImportError:
     from functools import cache  # type: ignore  # Python 3.9+
+except ImportError:
+    try:
+        from functools import cached_property as cache  # type: ignore  # Python 3.8
+    except ImportError:
+        from functools import lru_cache
+
+        def cache(call: Callable) -> property:  # type: ignore  # Python 3.7
+            return property(lru_cache()(call))
 
 
 Data = Union[str, bytes]