very simply version

game_backuper/hashl.py

@@ -0,0 +1,12 @@
+from hashlib import sha512 as _sha512
+from base64 import b85encode
+from typing import BinaryIO
+
+
+def sha512(b: BinaryIO):
+    s = _sha512()
+    t = b.read(1024)
+    while len(t) > 0:
+        s.update(t)
+        t = b.read(1024)
+    return b85encode(s.digest()).decode()