Adding general exceptions.

diff --git a/exceptions.py b/exceptions.py
new file mode 100644 (file)
index 0000000..3ce94d3
--- /dev/null
+++ b/exceptions.py
@@ -0,0 +1,13 @@
+#!/usr/bin/env python3
+
+class PreconditionException(AssertionError):
+    pass
+
+
+class PostconditionException(AssertionError):
+    pass
+
+
+class TimeoutError(Exception):
+    pass
+