Add notes

src/pis.py

@@ -1,7 +1,7 @@
 import yaml
 
-def load():
+def load():  # Programatically add a `toc` field to each entry.
-    with open("../data/pis/gwr-west.yaml", "r") as data:
+    with open("../data/pis/gwr.yaml", "r") as data:
         try:
             pis = yaml.safe_load(data)
             print(pis)