diff --git a/src/data/roadmaps/python/content/functions-builtin-functions@-DJgS6l2qngfwurExlmmT.md b/src/data/roadmaps/python/content/functions-builtin-functions@-DJgS6l2qngfwurExlmmT.md
index 46d704511..bea7892b6 100644
--- a/src/data/roadmaps/python/content/functions-builtin-functions@-DJgS6l2qngfwurExlmmT.md
+++ b/src/data/roadmaps/python/content/functions-builtin-functions@-DJgS6l2qngfwurExlmmT.md
@@ -15,3 +15,4 @@ Visit the following resources to learn more:
 
 - [@official@Built-in Functions in Python](https://docs.python.org/3/library/functions.html)
 - [@article@Python Functions - W3Schools](https://www.w3schools.com/python/python_functions.asp)
+- [@article@Defining Python Functions](https://realpython.com/defining-your-own-python-function/)