fix: wrong data type in cell

module2/exo3/exercice.ipynb

@@ -78,10 +78,8 @@
    ]
   },
   {
-   "cell_type": "code",
-   "execution_count": 17,
+   "cell_type": "markdown",
    "metadata": {},
-   "outputs": [],
    "source": [
     "## Traçage des données"
    ]