Add todo item about interview with Gang of Four

brandon-rhodes · brandon-rhodes · commit 4ac1fd7c352c · 2019-08-17T14:08:53.000-04:00
diff --git a/todo.txt b/todo.txt
@@ -126,3 +126,6 @@ mix-in classes “use mix-ins like this”
 “class registration”?!
 __set_name__
 subprocess.run
+
+Add a reference to: (and credit the tweet that mentioned it)
+http://www.informit.com/articles/article.aspx?p=1404056
