add missing module

src/pycalver/utils.py

@@ -0,0 +1,24 @@
+# This file is part of the pycalver project
+# https://github.com/mbarkhau/pycalver
+#
+# Copyright (c) 2018-2020 Manuel Barkhau (mbarkhau@gmail.com) - MIT License
+# SPDX-License-Identifier: MIT
+import typing as typ
+import functools
+
+# NOTE (mb 2020-09-24): The main use of the memo function is
+#   not as a performance optimization, but to reduce logging
+#   spam.
+
+
+def memo(func: typ.Callable) -> typ.Callable:
+    cache = {}
+
+    @functools.wraps(func)
+    def wrapper(*args):
+        key = str(args)
+        if key not in cache:
+            cache[key] = func(*args)
+        return cache[key]
+
+    return wrapper