Fix

src/datasets/dataset_dict.py

@@ -56,19 +56,16 @@ def _check_values_features(self):
                     f"All datasets in `DatasetDict` should have the same features but features for '{item_a[0]}' and '{item_b[0]}' don't match: {item_a[1].features} != {item_b[1].features}"
                 )
 
-    def __del__(self):
-        for dataset in self.values():
-            if hasattr(dataset, "_data"):
-                del dataset._data
-            if hasattr(dataset, "_indices"):
-                del dataset._indices
-
     def __enter__(self):
         return self
 
     def __exit__(self, exc_type, exc_val, exc_tb):
         # Here `del` is used to del the pyarrow tables. This properly closes the files used for memory mapped tables
-        self.__del__()
+        for dataset in self.values():
+            if hasattr(dataset, "_data"):
+                del dataset._data
+            if hasattr(dataset, "_indices"):
+                del dataset._indices
 
     def __getitem__(self, k) -> Dataset:
         if isinstance(k, (str, NamedSplit)) or len(self) == 0: