diff --git a/README.md b/README.md
index a9aabc6c2e235588adf504aac6262b66471f4476..5ff22f73158c4e60d80b91184be33497c8aefe66 100644
--- a/README.md
+++ b/README.md
@@ -15,6 +15,15 @@ In this tutorial we use Python 3.7 or higher. Make sure it is properly installed
 We assume that `git` is installed, and that you are familiar with the basic `git` commands. (Optionnaly, you can use GitHub Desktop.)
 We also assume that you have access to the [ECL GitLab](https://gitlab.ec-lyon.fr/). If necessary, please consult [this tutorial](https://gitlab.ec-lyon.fr/edelland/inf_tc2/-/blob/main/Tutoriel_gitlab/tutoriel_gitlab.md).
 
+**Important note**: In this tutorial, you will be asked to write functions. If you want to test the correct operation of your functions in the same file, you must use the statement ``if __name__ == "__main__":`:
+
+```python
+def func():
+    ...
+
+if __name__ == "__main__":
+    func()
+```
 
 ### README