First implementation (#1)

Reviewed-on: #1

tools/oracle/__init__.py

@@ -0,0 +1,13 @@
+"""The reference computations behind every expected value in this repository; see tools/README.md."""
+
+import importlib.util
+import sys
+
+if sys.version_info < (3, 14):
+    sys.exit("The paperspec tools need Python 3.14 or later; this is Python %d.%d." % sys.version_info[:2])
+
+_missing = [m for m in ("cryptography", "jsonschema") if importlib.util.find_spec(m) is None]
+if _missing:
+    sys.exit("The paperspec tools need %s %s; run them through pixi, or install %s with pip."
+             % ("the package" if len(_missing) == 1 else "the packages", " and ".join(_missing),
+                "it" if len(_missing) == 1 else "them"))