Return a Tuple, not a List

rapidsai · Feb 14, 2022 · 6768825 · 6768825
1 parent 1c73cc0
commit 6768825
Showing 1 changed file with 6 additions and 6 deletions.
diff --git a/python/cudf/cudf/core/frame.py b/python/cudf/cudf/core/frame.py
@@ -90,22 +90,22 @@ def _num_rows(self) -> int:
         return len(self._data.columns[0])
 
     @property
-    def _column_names(self) -> List[Any]:  # TODO: List[str]?
-        return list(self._data.names)
+    def _column_names(self) -> Tuple[Any, ...]:  # TODO: Tuple[str]?
+        return tuple(self._data.names)
 
     @property
-    def _index_names(self) -> List[Any]:  # TODO: List[str]?
+    def _index_names(self) -> Optional[Tuple[Any, ...]]:  # TODO: Tuple[str]?
         # TODO: Temporarily suppressing mypy warnings to avoid introducing bugs
         # by returning an empty list where one is not expected.
         return (
             None  # type: ignore
             if self._index is None
-            else self._index._data.names
+            else tuple(self._index._data.names)
         )
 
     @property
-    def _columns(self) -> List[Any]:  # TODO: List[Column]?
-        return list(self._data.columns)
+    def _columns(self) -> Tuple[Any, ...]:  # TODO: Tuple[Column]?
+        return tuple(self._data.columns)
 
     def serialize(self):
         header = {