-1 from length to avoid edge case overflow

Author: decantr

joke.py

@@ -7,4 +7,4 @@ def getJoke():
     # return a random joke loaded from the data.json
     with open('data.json') as data_file:
         data = json.load(data_file)
-    return data[randint(0, len(data))]
+    return data[randint(0, len(data) - 1)]