Update isolet.py

isolet.py

@@ -76,4 +76,7 @@ class Isolet(datasets.GeneratorBasedBuilder):
 
     def preprocess(self, data: pandas.DataFrame, config: str = DEFAULT_CONFIG) -> pandas.DataFrame:
         data.columns = [str(i) for i in range(618)]
-        return data.astype({"617": "int"})
+        data.iloc[:, "618"] = data["618"].apply(int)
+        data = data.astype({"617": "int8"})
+
+        return data