diff --git a/Tp4/etudiants/etudiant.py b/Tp4/etudiants/etudiant.py
old mode 100755
new mode 100644
index cc793f301bcaed1c9dfc4e23087c1c2b8e0fb375..2fc9043e001dcb650d000ba65934b6835422336d
--- a/Tp4/etudiants/etudiant.py
+++ b/Tp4/etudiants/etudiant.py
@@ -167,10 +167,10 @@ def ensemble_des_formations(liste: list[Etudiant]) -> Set[str]:
     $$$ ensemble_des_formations(COURTE_LISTE[0:2])
     {'MI', 'MIASHS'}
     """
-
-    formations=Set()
+    res=[]
+    
     for etudiant in liste:
-        formations.add(etudiant.formation)
-    return formations
+        res.add(etudiant.formation)
+    return res
         
                         
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