add yaml helper script; refactor python testing

pytest.ini

@@ -0,0 +1,27 @@
+[flake8]
+exclude =
+    .venv
+    */site-packages/,
+    */source-packages/,
+    */__pycache__
+show_source = true
+max_complexity = 12
+max_line_length = 200
+statistics = true
+doctests = true
+
+[pytest]
+python_files = *_test.py
+python_classes = Test
+python_functions = test_*
+norecursedirs = site-packages
+
+[report]
+exclude_lines =
+    if __name__ == .__main__.:
+
+show_missing = True
+omit = 
+    *_test.py,
+    */site-packages/*,
+    */source-packages/*